I will say this, growing up in Philly area where lacrosse has always been popular, freshman teams were never a thing, for baseball or really any sport. I don't believe I had ever heard of straight freshman teams until I moved to Ohio. I graduated in 95 for reference. Memories a little fuzzy, but I don't remember there ever being anything even remotely close enough to field a freshman team at my high school.
With all that said, my school never had freshman for any sport. A lot of that may have had something to do with it being a mid size school usually graduating around 250, and they also offered pretty much every sport, club, and after school activity you could think of. Sports waaaaay outside the norm. We had hockey, crew, bowling, archery, even equestrian. Yea, horses and ish lol. So kids had tons of options for things to do outside of your standard sports.