Originally Posted by
Inversed
There is still a paradox to it all when you try to look at it too hard. Spider-Man is a popular character, he's been around for a long time and people feel he should get some attention in-universe among the superhero community, so put him on the Avengers. But they don't want him to lose his underdog status, and to take all the attention away from the other characters, so just have him be around or for comedic relief. Bendis' Avengers is really the only time we got to see him on the team for a significant amount of time, and I thought he was used decently well, wasn't really a major focus but bounced off the rest of the cast pretty good. (And I would say JMS and Slott both made great use of his Avengers status in their books). Hickman's Avengers he was almost immediately replaced by Otto, the Mighty Avengers he actually proved very effective, especially during the Axis crisis, and he left the Unity Squad in the first issue. Waid's Avengers did make a good reason for him to be involved, being the new funder through Parker Industries, the problem was how he was mainly treated as an ineffectual dope and punching bag for Nadia "Loves Everyone" Pym (all for a repeated joke that never made sense)
But the thing is, I wouldn't say this is really about solo heroes being lesser because they don't connect to other characters because that's far from the truth. I mean really, no matter how hard you try, you can't look that way with Spider-Man, especially 616 Spider-Man. ISSUE 1 of ASM is him trying to join the Fantastic Four, he pops up in so many other books, and others pop up in his all the time. And then you have Marvel Team-Up, which is a whole book of just Spider-Man interacting with other MU characters. Pretty much everyone has interacted with him at some point or another, he's been everywhere. And I think that's what makes this question of the OP most interesting, because based on his history, it is understandable why some would wonder why it is not more respected or recognized among the community given his relationships, no matter what they may be exactly.