I'm having this problem as well. When it comes to hardware I'm competely illiterate and just can't do it.
I find abhorrent that Cryptic/PWE have released Season 7 with so many bugs and glitches- essentially rendering the game utterly unplayable for a large number of players. I find even more disgusting that they have failed to act on the problem with today's patch update. It is apalling and insulting customer service and I find it very disturbing that non of the devs have even commented on the situation. Disgraceful.
I for one am seriously considering stopping playing this game.
After two days of not getting past the loading screen, i tonigh unistalled the game and re-installed direct from the sto site. I'm glad to report i have successfully logged in. I'll post updates of how i get on, i.e if i suffer crashes during gameplay etc.