I'm not saying PFF is perfect, for me especially because they don't account for level of competition, but I am saying it's way better than me/average fans in analyzing player performance.
I don't think it will matter as those of you who are negative on PFF seem pretty dug in, but some stuff I found on the internet seems to say all nfl teams use PFF to some extent. If it's good enough for them . . . :
"Rams head coach Sean McVay, meanwhile, hired PFF senior analyst and former NFL QB Zac Robinson this offseason to be L.A.’s assistant quarterbacks coach. Robinson had been watching and grading every QB snap for PFF, and his knowledge of the position and the Rams’ offense impressed McVay" - 2019
"4. Conversely, the value of the data in those areas is proven in that nearly the entire NFL has subscribed to Stats LLC and/or Pro Football Focus, and some rely on smaller services, like Pro Scout Inc., which is run by 64-year-old former Utah coach Mike Giddings." - SI 2017
"One commonality? Most subscribe to services. Cincinnati-based Pro Football Focus now lists 27 teams as clients, and founder Neil Hornsby says, “I’d be surprised if we haven’t got 32 of 32 by next season, if not this season.” -SI 2017
"Owned by broadcaster and former NFL player Cris Collinsworth, PFF works with all NFL teams and more than 95% of the Power Five colleges." - 2022
"The Cris Collinsworth-led Pro Football Focus is a leading provider of advanced analytics in use by all 32 NFL teams, 130 FBS college programs and 42 FCS teams. - 2023 article
"The Cincinnati-based football analytics company, under celebrity owner Cris Collinsworth, counts every NFL team as a customer. It charges each of them $150,000 annually for its services, including its golden ticket: a proprietary, labor-intensive player-grading system." - 2024