I did gymnastics in the early 80s. I was competent, but not brilliant - in the squad of a big club, but very much making up the numbers. It was still pretty brutal - being forced into splits etc. I gave up at 10 when they said I was going to have to train 6 times a week or not at all.
My own DC (boys) drifted into gymnastics through soft play classes - I was never particularly invested in them doing it, but I wasn't against it, as it was clear that their club was very, very different to what I remembered. One DS is now at elite level - regional squad and national finals. One is somewhere between competitive and recreational - occasional local competitions, but not particularly bothered either way. The youngest is only just starting proper classes.
We have now had experience of 3 clubs (a lot of gyms in this region have had to stop doing competitive boys' gym, due to lack of coaches or uptake) and, while I have never seen anything that concerns me at all - lots of transparency, feedback etc), it does seem to me that there is a different culture around boys' gymnastics. It may have something to do with the fact that a lot of the boys' coaches come from overseas, often with a background of having themselves competed to a high level in notoriously abusive programs. DS1 has been coached by three former Olympic medallists from regimes known for treating young athletes appallingly. They were all extremely cautious with the boys' development, and very much in favour of slow, steady progress, without them being pushed early on. They were particularly careful around growth spurts. The boys' hours went up only after lengthy discussion with the parents, and other options were always available for those who did not want to take the next step. They were extremely careful about injury - DS1 was asked to see a physio after an injury, before his coach would agree to take him to a competition.
There seems to be less emphasis on body-conformity with the boys. Obviously, the coaches are looking at physiology, strength etc, but there does seem to be much greater variation in the build of the boys who compete with DS1 - possibly because the different pieces favour different strengths.
A previous poster mentioned clothing differences. I have always been uncomfortable about the way boys' gym showcases strength and power, without any of the decorative stuff - plain leotards and shorts, no music for routines, no dance elements - while the girls are expected to look nice, smile, and do lots of dancing around between the main skills. It always feels as though the girls are being treated as show ponies to some extent, while the boys are allowed to just get on with the main 'business' of gymnastics. Having said that, I have noticed what looks like a change coming through in girls' gym - the young teen girls I see training now look stronger and healthier, and often taller or bigger built - than was the norm even a few years ago.
Maybe we've been lucky in our region - and maybe there is a clear difference in culture between girls' and boys' programs, but there certainly are clubs getting it right. Hopefully, with people speaking out now, pressure will be put on the other clubs to improve.