If he is, it’s not by much.
As of 2017, when Crosby had played fairly close to Forsberg’s career game totals, Crosby was 3rd all time in adjusted points per game with 1,46, Forsberg was 4th all time with 1,38 despite being older when retiring than Crosby was in 2017 and playing more games injured and not being 100%.
Forsberg is also 9th all time in playoff ppg with 1,133 through 151 games, Crosby is 11th all time with 1,125 through 168 games (don’t know the adjusted numbers for playoffs but they’d surely work in Forsberg’s favour). Forsberg was also the only player to win the Stanley cup scoring race without reaching the finals in history, and he did it twice.
I wouldn’t call that a different tier for Crosby. They are clearly in the same tier ability wise. Anyone claiming otherwise looking at these numbers is absolutely beyond me.