It's not just team sports.
Gymnastics is crazy as well.
My daughter is 6yo (going into 1st grade).
Some of her friends are pretty good at gymnastics.
They are on the "pre-squad" next year and will even have competitions this upcoming year.
They have 9 hours of practice/training per week starting in August.
At 6 years old.
That's more than I had basketball practice in HS I think.
Our daughter recently tried out for a lower program at the gymnastics gym - but they didn't say what the time commitment was other than it's a full year expectation (not like her normal classes where she can drop at anytime).
We're waiting to hear if she made the team or not.
We are lucky in that both our kids are well advanced for their grade levels so significant sports time commitments shouldn't be a problem yet.