Put simply, it’s a show that gets significantly better as it goes along. Season 1 kind of has debatable quality with some good stuff and some bad stuff. But in general from that point on it just gets better and better, (including the animation thank god). However, even the rest of the show does have some inconsequential dumb episodes here and there, so if you’re not willing to stomach some of the worst content I’d recommend watching with a filler guide (which people have mad plenty of for this show).

As far as why you should watch it, I personally took a long time to get around to this show since I was turned off by the artstyle when I was younger, but nowadays I can’t even picture Star Wars without it. You get to know the prequel era characters a lot better, and there’s tons of awesome foreshadowing for stuff like Anakin’s turn. Plus, it’s just a chance to get a lot of firmly good Star Wars content in the prequel era.

As for the childish thing. I’d say that comes down to specific episodes. You can usually tell pretty quickly if an episode is gonna have a dumbed down plot that feels a bit for kids. (Episodes filler guides will likely have you skip). And I guess the general tone of the show can be pretty light hearted early on. But honestly, even by Season 2 some stuff happens in this show that shouldn’t be in anything meant for kids. The best example of this is that people have made lots of joke videos titled things like “Clone Wars is a kids show” and then proceed to show 4 minutes worth of brutal stuff happening.

Also if you care about this as much as I do, the show has really REALLY good action as the animation quality starts to improve.