I literally ran into Matthew McConaughey years ago in a Chicago Hotel, and he seemed much shorter than I expected. He says he’s 5’11" but I’d put him at 5’9" tops!
My daughter listed her height an inch shorter for a while…she felt like she was often one of the tallest in the room at 5’7" which was closer to 5’10 with character shoes. Grass is always greener I guess.
True story - I ‘stretched’ over a half-inch as an adult practicing yoga 3 times a week!!
I think most people would agree that the MT business is unusually “-ist” relative to most careers; size-ist, sex-ist, beauty-ist, age-ist, voice-ist, connections-ist, fame-ist – you name it – and I’d guess some MT programs reflect this if their goal is produce working grads. And since (sadly) women are overall in far lower demand than men in the industry (~2/3 of the paid weeks go to men, who are outnumbered by women by at least 5:1 at most auditions) I’d say it is even more true for women.
Our D (a 5-6" ingenue-type who has been a paid MT for the past 3 years) frequently finds herself in callbacks with 5-10 women who are remarkably similar to her in all respects, but I would say height relative to the male ingenue is (sadly) frequently a driving factor in final casting. As far as I can recall she has only once been cast in a production where she was taller than the man she played opposite, and that was in a comic role (plus the man went straight to Broadway so he is exceptional in all respects).
I’d say at 5’6" it seems D may be on the tall side for most on-camera work, where head size (who knew?!!) is yet another significant characteristic. Apparently males are supposed to have larger heads than their on-screen female counterparts? I do think the ability to play young can be a huge asset to recent grads, as they otherwise find themselves competing with 40-year-old actors with amazing skills, resumes, Twitter-followers and connections.
I’d also guess – though I have less experience with this – that there might be varying markets with respect to height requirements. For example, I’d guess Broadway can hire exactly the shapes and sizes they want while local community theatres may not be able to be as selective. As an example, I know once D was in final callbacks as a Broadway cover where she needed to have the EXACT measurements of the woman she would cover as there were a lot of costumes.
Since height is among the things it’s very hard to change, the common wisdom that all you can do is be the best version of yourself that you can be is ultimately really the only way to think about this. I suppose fudging height on resumes might conceivably get you in the room a bit more often, but once you’re paired with potential castmates the jig is up. 
Ultimately the ideal solution to the entire “-ist” reality is to be like @soozievt’s D and create your own brilliant material and career, or maybe become LMM’s muse.
Thanks @MomCares - that’s the kind of “beyond-the-college-audition-realm” insight I was was looking for
My D would love to play a Disney princess but at 5’9" she’s too tall.
As a former 5’10" actress I feel her pain (and as I understand it the Disney height limitations are very real) but on the bright side, since most Disney princesses are between 18-24 years old, by the time our girls are out of college they have already used up most of their princess shelf-life I suppose.
While on one level being a classic ingenue/princess type and height may seem to be an early advantage, remember that there is always a younger fresher-faced crop coming into the marketplace, while for those who play character or older types job prospects may steadily improve as they age into their type after much of the competition has already moved on to other careers. As with most things in life, type is a mixed bag.
My boys would say being tall is an advantage for MT boys to play most leading roles and some dance parts – at 5’8’-ish, they tend to be on the shorter side at auditions. Now, I’m not a professional – and this is not a 100% rule, but my general observation is that if voice/dance/acting skills are similar, the boy who is taller and more built (think “Gaston” – very manly) seems to get the part. Height/build can convey the optics of power, age, maturity, sexiness, strength, etc. There are a lot of young, lean/thin, medium-height tenors out there; so a tall tenor/baritenor with a great physique may have a bit of an advantage. Also for big dance shows; height is a factor for partnering. Unless there’s a sight-gag planned, boys need to be taller than the girls in medium heel, and fit enough to do lifts, etc. One of my sons got cut from a dance ensemble at school and was told he just wasn’t tall enough to partner the girls they’d selected. All good – move on. Actually, for him it was nice to hear the real reason for the cut that time.
(FYI, this is still me, @MTTwinsinCA, but my login won’t work on any device, hence new screen name)
Found this thread as I was looking for something else and will add my daughter’s experience. Her school employs a coach that is a former casting agent that guides them throughout college. He told my daughter that although she has the look and the sound of an ingénue, but she is just too tall. 6’1 in character shoes. She has since rebranded herself: spent a summer studying musical theater improv and standup, and is now marketing herself as the “funny girl” That kind of honest guidance early in college has been so helpful. And she seems to enjoy it more.
For instance, a recent touring production of Into the Woods listed all the princess height limits as 5’6"
My daughter is a 6’ redhead in her stocking feet. She did a 7 week summer acting intensive and several casting directors came in and gave all the actors their opinions on roles and types. My daughter was told the same thing as yours. Go funny girls!
I do think there is bias against women/girls that are too tall and men/boys that are too short, at least in terms of adult roles. This is not just in MT, but for acting in general. For Acting, Sophie Turner of Game of Thrones is listed at 5’9” tall, but seems to tower over some of the males in the cast listed between 5’8” to 5’10” like Kit Harington (5’8”) and Aiden Gillen (5’10”).
I think in a dance heavy show, a small girl would have an advantage – it’s easier to lift or swing around a 5’0” girl that weights 90 something than it is to do the same with a 6’0” girl that has the same build, but is 140 because she’s a foot taller. And, similarly, it would usually be easier for a burly 6’2” guy to lift and swing around a girl than it is for a slim 5’6” guy.
(As an FYI, I also did some part-time sports writing back in the 90s and I am positive that almost every NBA player out there is shorter than what the NBA lists as their heights by a good 2-3 inches, and sometimes more. Granted a guy listed at 7’0” by the NBA but is really 6’10” is still gigantic, but 7 foot tall is better for marketing. So, it’s not just the acting world.)