I do think there's some misconception about homeschooled and online schooled kiddos. There are a lot of these kids that are quite socially active outside the gym. My DD participated in an art class all year, attended many workshops, and got to choose project topics that she was interested in and learned a LOT by exploring things she had been interested in. She also had the opportunity to do some volunteer work.
Had she been in a regular school program, she would not have had those opportunities due to lack of time.
Anyway. My intent is not to promote homeschooling here. Back on to the original topic, my kiddo is an 8th grade possible L8, so we have no horse in this race, nor do we have personal experience juggling an upper level college hopeful. But she did not directly homeschool because of gym per se. More because she wanted to have the time for additional experiences outside gym and school. And maybe to sleep a little more.
Of course homeschooling isn't required for college. To my knowledge, I don't think many area clubs even have homeschool programs, including DD's gym unless it's secret.
They've placed kids in D1 programs. But I can understand gyms that have these daytime program, as the best, most senior coaches can probably avoid working so many evening hours. And gymnasts and their families have time together, or have time to do other activities outside the gym.
I don't think that one is inherently better or worse. IMHO I think it depends in what the gymnast and family needs, and how that aligns with a gym.
Gym often requires a number of sacrifices as you progress through the levels, particularly for college (or elite) hopefuls. That said, so do so many other activities.