I’ve heard other people make the comparison between Batman Beyond and Spider-Man. You can see it relatively clearly and they even homage ASM #33.
Personally I like most of the DCAU shows other than Zeta Project and Static Shock and for one of those I never really saw it and the other one just didn’t resonate with me.
I enjoy the legacy aspect of Batman Beyond a lot, similar to why I like Spider-Girl. It seemed a generally organic projection from where we started out with TAS moving into the New Batman Adventures.
In some ways I think JLU is actually better than B:TAS but I think that’s not really fair since they were trying to be incredibly different things.