With this, both companies have egg on their face.
On Disney- why did they have to change the deal and ask for more (WAY more)- just keep the good thing going. Even if your cut is small on the solo Spidey films, you get the merchandising, and you get the character to appear in your other films, which is huge selling point since you basically set up the character as Iron Man's successor in the MCU.
On Sony- lets get real guys- you don't have what it takes to make a good Spidey film and you need Feige/MCU. That 1 billion + gross is all about being part of the MCU and coming out in close proximity to endgame and being a follow up to it. Yes Spidey is popular, and you had a hit with Venom (since there was a lot of pent up demand for the character), but you aren't going to see remotely the same success if you leave the MCU. Audiences are reasonably smart- if you want to see an example of what happens to a comic property that is part of what is perceived to be a lame duck universe- go look at how Xmen Dark Phoenix did. While I don't believe a newly isolated Spidey film (with no Stark reverence, no Happy, no ties to pretty much ANYthing that happened in the previous two films) will do that bad, but you will not see success anything close to what you had from Far From Home or Homecoming.
Both sides need to come to their senses, and come back to the table (and hopefully agree to just move forward with a deal close-ish to the original agreement they had.