I believe in supporting long term outcomes over short term outcomes. This means that I support unpaid internships, volunteering, arts residencies and so on in the interest of long term career success.
This strategy worked in high school by helping my kids get scholarships (or admission to schools with great aid), and worked for grad school by securing funding. The scholarships far exceeded anything they would make working locally. I did not worry about their work ethic. (I personally think that working locally should be honored more in merit applications, as an aside.)
We avoided debt with the exception of one child who was in a lucrative field and had well-paid summer internships, and he paid off his $10k loan once he graduated. Because of his field, he was also able to contribute more to his college costs. We did not ask this of him, he just did it.
Two of my kids have serious health challenges. One took quite a bit longer than 4 years to graduate (at a top college), and would never have been able to work and do school at the same time. I paid for everything, basically, that was not covered by scholarships. I just want to introduce this kind of reality into the discussion because many on this board deal with it. (The perseverance shown by some of the kids with health issues while in college certainly makes the phrase “skin in the game” seem trivial.)
The other child w/health issues went to LAC, then community college, now LAC p/t program for working adults and works hard and long at a low level job that she takes pride in. Her entire teen age years were spent on a performing art, sometimes in elitist environments. Her work ethic is nevertheless outstanding. She tolerates a monthly amount from me but values financial autonomy, and I literally try to sneak money to her (taking her out to eat for instance.)
None of my kids learned to drive as teens. Two still don’t drive and don’t have cars. This saved money.
For various reasons (husband’s stroke) we sold our house and that has helped a lot. I continue to try to help those of my children who need help financially, and support opportunities to grow in their fields- as much as I can and when they let me! I do not worry about affecting motivation for self-support.
Overall, I like values to emerge from my children rather than force values with my own requirements. It is still a work in progress, but so far so good.
I think that for all of us, the philosophy will vary, but consistency is important. I have seen all kinds of arrangements have great results for kids when it is clear what they can expect and when they receive our emotional support at the same time. So honestly think you can probably answer your own questions since you have clearly done a good job so far.
(editing to add, however, that others with different philosophies expressed in this thread have also done a good job, and if their answers involve disagreement with your way of doing things, take it as information not argument- since you asked…)