I think another issue Toy Story 4 had was the side characters. The old cast just sits in the RV and has three to four lines at best for the entire movie. Then there's the new side characters (McDimples, Ducky and Bunny, Kaboom, etc). You keep waiting to find out what purpose these guys serve, but you never really get your answer. They have one, maybe two short scenes dedicated to them and they either play comedic relief in the background or just exist for the rest of the movie.
Basically, anyone who isn't Woody, Bo, Forky, Gabby Gabby, and to a lesser extent Buzz gets hardly any meaningful screentime.