Is Disney+ worth it?

If you don't have any other streaming subscriptions then yeah, I'd say go for it. But imo Netflix is still a better investment for now.

I've had it for a few months now, and while The Mandalorian is fantastic, and there's a really interesting Imagineers documentary, those are the two platform exclusive shows that are worth it, tbh (And the free youtube channel Defunctland makes amazing 20 min documentaries about old theme park rides and imagineer drama). Almost everything else is readily available through cable or pirating or even just digging out a childhood DVD/VHS.

But if you have the extra cash, buy the hulu/espn/disney bundle, or split the account with a friend or two.

To quantify though, I'm a disney fan but probably only sit down to watch a disney movie once a month if that. If you're someone who'd watch disney/pixar more frequently, then it might be a good way to go.