Let me break it down for you. When the top teams leave to another league, your league is de facto the lower flight.
One of the downsides of being in a lower flight is that you don't have the same opportunity to play the top teams and demonstrate comparable worth, like you clearly enjoy. Without the opportunities to play better teams, the experience gap widens between the lower flight players and the higher flight players.
Slammers Fullerton was clearly not getting enough from playing in Discovery and took the first chance to jump ship. Discovery is worse for the loss.
But, if that doesn't bother you or your young player, don't worry about it.
Well that’s obvious that Discovery got weaker in this age group with the top 2 teams leaving (Tudela is playing up in the 06) but that wasn’t the question I answered (or couldn’t answer)
They also expanded from 21 to 28 teams which dilutes the league a bit.
Most of the socal E64 teams were NPL teams last year so it remains to be seen if the competition is better. I believe it will be since all the teams are from the top half of Discovery, but we will see.
Philosophically I don’t like any of these club based leagues, including the ones my kids play in, but that’s a different thread.