Pitch count question for 9U/10U

I'm 45 and pitched as a player when I was a kid through HS. Pitch count wasn't ever discussed back then that I remember. But, I also don't remember travel teams being a big thing or even existing. It was more like, baseball then all-stars, then on to the next sport so parents could keep dropping off their kid for a few hours a week lol.

It stands to reason that if pitch count is controlled in games, I should also be cognizant of it in practice. I understand drills are different but full speed pitches apparently need to be kept within certain limits. When I was a kid pitching, the limit was "quit being a bitch and keep slingin or little Billy over there is gonna take your spot". These days, what is that limit for each age group? limit per day per week, etc.

Respectfully- thank you in advance