If Potter doesn't change the trajectory Chelsea took under Tuchel, he won't have another season. These are the modern realities - you do not have time to "prepare", you must immediately show at least some result, and if it is good, you have a chance to work further to show an even better result.
Signing Ronaldo will most likely be a marketing ploy, but with all his age he has not lost his sense of goal and he still has a shot, so in some games even without playing all 90 minutes he can be useful.
I think Chelsea would be foolish to sign Cristiano Ronaldo at this moment. Because Cristiano Ronaldo is not performing well at the moment, one of the examples of which is that he was not included in the starting XI of his home country Portugal's World Cup match. Because Portugal's coach knows that Cristiano Ronaldo's legendary style of play no longer exists.
If we take only marketing goals, then it does not matter how Ronaldo plays. He remains one of the most popular athletes worldwide. Chelsea will buy him for free, which may not be such a stupid decision even if Ronaldo keeps his huge salary. And I don't think that Ronaldo is already that bad (more precisely, he became bad in just a year) - last year he was the top 3 scorer in the Premier League and this year he is retired? Hard to believe.