If you’re a club who are rolling in money, you replace a player like McGoldrick with someone who can also finish brilliantly (and you replace Egan with someone who also passes brilliantly; and Norwood with someone who doesn’t have the odd bizarre off-game; and Stevens with someone who can also kick it with his right foot ... etc.)
If you’re not rolling in money, you try and train Egan what exactly to do when he’s got the ball at his feet; and you work with Norwood on concentration or approach or focus or whatever weirdly goes awry sometimes; etc. etc. ... and you work on McGoldrick and confidence/ decision-making / technique in front of goal or whatever it is to try and improve his performance.
We have good players (and McGoldrick’s one of them), but there’s a reason they all play in the championship and not the champions’ league. Where a coach at this level earns his money is making the most of the best bits of every player’s game, and improving the worst bits, and combining everything as well as possible to get the most from the team. Wilder and Knill have done this extremely well at United.
Just buying someone better is the other option, but it’s an option that’s only available to clubs who currently have a massive bank balance - not us. It’s also still a risk as a new record signing may get injured, fall out with the manager, or turn out to not be as good as everyone thought. Recent experience suggests buying players in January can be pretty hit and miss in terms of genuinely improving the squad. Our summer acquisitions seem to be significantly better in this regard, and I’d include McGoldrick in that as he’s played well in most games, helped us create chances, and contributed to the team reaching a very decent position in the table at this point in the season.