Yeah - I agree with this, though I think the quarterback essentially sets a base.
Just looking at Brady, for example, I believe he has roughly a base passer rating of about 90. That is, put any level of skill players around him, even bad ones (like 2013, 2006), and he’ll probably put up a rating of 90-95 at a minimum with these current rules. That’s over a full season with all its ups and downs, garbage time included, etc.
Put some decent players around him, though still some issues, you get a passer rating closer to 95-100, like last year, where we saw a mixed bag.
Very good supporting cast, though not without some flaws (like 2017) and we’re at 100-105.
Great/elite skill players and protection and we start getting to that 110 and above level. 2007, 2010, 2016.
Brady is the same QB every year. The passer rating variation is all about the talent around him, and it has a range of about 20 points, which is a huge deal. On average it’s close to 100, so right in the middle of the range.