I do agree that Stan Lee would probably be miffed by this...it might not even be happening if he were still alive today to weigh in on the issue.
But apart from that, I'm not really all that concerned? ^^; I mean, it's not as if there'll be a stalemate and Spider-Man will be gone forever; no one in their right mind would let all that potential profit go to waste.
The only real creative problem is whether he will be allowed to participate in the MCU anymore, and I honestly couldn't care less about that. Spidey was around before it started, and he will most likely outlive it. I do understand how devastating it is for people who are particularly attached to the MCU and Tom Holland's Spider-Man, but I'm not one of them...so I just take a sort of 'nothing gold can stay' perspective on that. =T
In my mind, all it boils down to is who gets to slap their name on the credits, which doesn't really mean much in the grand scheme of things. Both Sony and Disney have people of talent in their employ, so it's not as if either's ownership will guarantee that Spider-Man will be handled well...or badly. Whatever happens in that respect, you won't see any tears from me.
My biggest concern, in fact, is whether this squabble will pressure Disney to try to buy out Sony, which could have huge repercussions down the road...