You are basing you whole position on a 60 game season.
If you really believe we were the 4th worst team in MLB, on paper, last year, then I can see why you might doubt we have any chance, but I do not think you are that short-sighted.
Your complete write-off of Sale shows your bias.
You have turned something that is unlikely into something that is impossible.
While many point to 2013 as that magical season where so many players had career years (actually not true), the 2021 season does not need "career years" from anyone.
We just need a few players to return to near their 2018, 2019 or 2020 season, and since only Ottavino is over 33 years old, it's not a stretch to have some optimism about making the playoffs.
You mentioned a few teams better than the Sox, on paper, but some of those teams got worse from 2020- the season you put so much value in.
If Sale comes back at a 3/4th level starter in July, that could be a huge plus. ERod & Richards replace guys like Mazza. Ottavino is a plus. We lost no significant pitchers.
EHern & Renfroe vs JBJ is questionable, but certainly not a clear step backwards, and besides, had we kept JBJ, you'd be projecting a decline from him anyway due to his age and loss of a step on defense.
Devers dipped a little, last year, but did well near the end. He could and even should provide a big boost to 2021. He could even have a career year. Bogey is peak prime. Verdugo is just reaching peak prime. You cat like it's impossible for 2-3 of our players to have great years, when JD, Verdugo, Bogey, ERod, Sale, Richards (maybe not so recent) and Devers have already had very good to great years very recently and guys like Beni, Vaz, Ottavino, Barnes and Renfroe have had very nice seasons very recently.
It won't take a miracle to make the playoffs- just a return to or near prior form of enough current players. Our core of good to great players is bigger than you think.
Now, can too many of these guys NOT return to or near form? Of course, and that is what you are saying is a slam dunk occurrence. Fine, that's what is expected of a Yankee fan, but deep down, I think you know our chances are better than you give us credit for.