With the way its gone financially under FSG, I'm not worried about the money, as I think we can afford the fee, it's only if he demands ridiculous wages that the deal won't happen. I'm pretty convinced in my own head that we've already sounded him out and we know where he will be in 2023.
With the money this generation are on, it's not like they need the money, so if they really loved the club etc etc. However, with that deal that Mbappe got, then the agents especially will be wanting their slice of that nice fat signing on fee, so no-one is going to sign a new contract to help the clubs out.
There's the agent piece for sure.
However, for the players, while they don't necessarily need the money, it's about choices. Salah on a free has a chance to move to more clubs than Salah leaving for 50/60/70 million+. Not saying he'll go there given their financial trouble, but the only way he's going to a club like Barca is on a free. He'd also seen Alaba getting his move to Real on a free. Even Sadio left because he only had 1 year left. No way he's going to Bayern for that fee if he had 3 years left for example.
The money helps, but so do the choices. If Lewandowski's contract ran out, he might've been a Barca player by now. But as it stands, Barca has to meet a Bayern valuation. Lewandowski's won everything with Bayern, but it's not like Bayern were just going to let him go for free.
Ultimately, if you're a big name player and want to get yourself as many options as possible? Run your contract down to 1 year or free. If you're a young talented player, negotiate a release clause or run your contract down anyway.