I don't like the WR room, but the massive cap hit entailed in trading Diggs significantly ties their hands for 2024. I don't get the sense Pegula is averse to spending on the Bills, though maybe the cost overruns on the stadium are creating a temporary money crunch, I dunno.
I do think there's a pretty good possibility the Sabres have been operating with an internal cap in recent years. The rumor is TP met with KA and his hockey guys to talk about some money implications to proposed splash moves this off-season. If that is true, it would mean he is now ready to spend more lavishly on the Sabres. A signal might be if they buy out Jeff Skinner, which may or may not be a good idea, but would probably be needed if they want to bring in a big fish.