I don't think that argument even has to be made.
If streaming weren't a thing, I'd be saying to wait to Red Box it.
We continue to go because the slate of animated movies is few and far between and we enjoy the disconnect from the outside world that watching something at home lacks.
We've seen everything Disney and Pixar has put out in theater since my son was born 11 years ago. (he slept quietly through Brave in his carrier while his mom and I watched) Onward is the last one from either studio that we've seen in theater that wasn't a disappointment and, If I'm being honest, I wouldn't say that one was great, either.
As for D+, we loved Luca. I liked Soul but he thought it was boring and I completely understand why. If I weren't closer to the protaganast's age, I probably wouldn't have liked it, either. I feel like Turing Red was saved a bad theatrical release by being put on Disney+ to shield it since I don't think they were ever going to get enough of the 25-35 female crowd showing up to compensate for the family audiences that would have avoided it.*
Instead, they can lament how good it might have done without having to answer for how it probably would have done.
They just don't seem to have it like they used to and others are stepping up to fill the space.
Heck, I love the Tom Holland Spiderman movies but even Sony, who'd been putting out stinkers before striking a deal for the MCU made what is in my opinion, one of the best super hero movies of all time with Into the Spiderverse only to top it with the sequel.
It's inventive and creative and touching in real ways that feel earned rather than contrived - everything I used to expect from Pixar.
Disney+ didn't cause that.
*as a reminder for everyone who loved it, that one doesn't even show up on kid's accounts on D+ which seems like a pretty strong admission from Disney about the audience they felt it was made for.