As to the first part of your post I will say generally kids these days are not living the same HS experience I had 30 years ago. I will say I worked in the summers plenty of hours once sports were done. I also worked my senior year of HS, but for the most part it was a blow-off year academically. I was only taking 4 classes.
My D19 was done with sports after Junior year. I had hoped she would have more time in the fall for the college app process, but she found herself another job that ate up time. Also it didn’t help that it was Fri/Sat in Oct, which meant no visits then. I will be honest it was tough getting her over the finish line, which extended in Jan-Mar because of additional scholarship competitions for schools and of course the local/national scholarships.
And in a effort to make as much money as possible before college she started taking on every possible job around. At one point she 21 private swim lessons going on. Through all her craziness starting the Summer after Junior year she will probably net $4-5K more than if she had taken it easy. Sometimes I just think these kids are used to being busy so that is all they know. A 11-12 hour day for her between multiple jobs is her normal.
All that being said I would try to rein the kids somewhat to ensure they had adequate time to devote to the apps.