Yeah it takes more kids in a class to field a team now days because so many either dont go out for sports, or they specialize in only 1 sport, and play it all year through clubs etc. So that drastically reduces the number of kids available for each sport.
I believe there are 2 more classes than when I was in school too, I believe they added 8 man and 5A since I was in school. Not sure when they were actually added. And with less and less participation in even 1 sport let alone multiple sports I think there has been discussions on adding even another class of 6Man or changing the 8 man to 6 Man.
I definitely know that school sizes that easily fielded an 11 man team 25 years ago, now are having difficulty filling out an 8 Man team, with the same size class, there just are not enough kids participating in enough sports.
Girls BB at many schools is now also having issues too because adding another sport (girls wrestling) at the same time has split the pool of athletes between 2 sports. Yes I think cross country may have caused this when it was added many places, but probably not to the same extent.
My kids middle school does early and late season in the winter, so they play BB before Xmas and Wrestling after. It gives kids a chance to play both and decide what they want to do for High School. It may be something that they do the same for High School as well some day, if it can be figured out.