Maybe someone with kids or those who know the academy system better put I don't think that our regular season is difficult. Our academy teams play an age under so U19 is actually a U17/18 team. However, we're the MLS academy in the area so player on our team are recruited to play because they want to make it in MLS. Other academies may be more local and have players that aren't MLS ambitious.
So our best games are during tournaments playing other professional academies.
MLS Academy teams are not always (and actually not usually at the younger ages) the best teams in the DA. Geography drives where a lot of players play and parents know that if their kid is top-notch they will get to where they are going.
I know some families in Westchester that declined NYCFC Academy invites for their U12-U15 kids due to the distance to the training, but some of those kids will likely end up there as juniors and seniors in high school
If (or when) the MLS Academies go residential there should be a big step-up and separation in their quality.