It's been 3 weeks since I last received a response from itch.io support for my project's  file size increase request.  Is this request also blacklisted or something? 

Ticket ID:307948

From what I've heard, Itch will only raise the limit if they think that your game will make enough money to justify the higher costs. I don't know how well your previous game did, but it might not have been enough to convince Itch to raise the limit for you. About no response, though, I have no idea.