As far as I’m concerned we’re stuck with him now till his contract is up in 2024, by which time he will be 29 and age may have wisened him, he’s still playing like a teenager, impetuous and raw - like Aaron Ramsdale has at times for B’mouth this season.
Assuming we were to move him on, who would he even go to? Nobody is paying £30m for Jordan Pickford anymore. There is far better value in the GK market than him.
So, assuming we got, let’s say £20m or so for him, you’re looking at teams beneath us in the league and even then likes of Dubravka, Fabianski, Pope and Ryan are better, more reliable keepers than him.
The market / game may change, he could yet improve as he’s young for a goalkeeper, who knows there may be a dearth of “decent” goalkeepers, in which case he may become a bit more of an asset.
In any case, in answer to your question, if we seriously aspire to higher than 7th, then no I don’t think he’s a long term solution and yes he is a problem.
In terms of urgency, Is he in the top 5 positions on the pitch that need to be replaced to get us back on the right path, absolutely not.