I don't see them moving, but I also don't see a new stadium; at least not downtown. The most likely scenario is a complete reno at the Ralph.
However, the OP is fully correct about the personal finances of WNYers. WNY is a wholly depressed economic area, akin to Cleveland but nowhere near as bad as Detroit. There just isn't many ways to make real money in Buffalo, and as such there isn't a lot of disposable income. How many people are going to buy PSLs? Not many. On top of tickets more than double the price. It's just not in the cards for Buffalo to get a new stadium. And as time passes the next generation is moving in and they are more against publicly funding a billionaire's play palace. In 2024 there will be very little support for a stadium using public funds; not to mention the downstaters not wanting to help fund a Buffalo-based stadium, and NYC wears the pants.
Erie County, with maybe 20% from NYS and the NFLs grant program, will go in with the Pegula's on a new no frills stadium near the Ralph or a full on reno. Buffalo is never getting a new state of the art stadium. Ever.