I agree that Crosby hasn't been great in the Stanley Cup finals. It's a legit strike against him. I still think he's done enough to be in contention for #5 all-time, but let's be honest about his shortcomings.
Crosby's 0.80 PPG in the SC Finals ranks him behind a lot of players who are either in contention for #5 all-time (Beliveau, Hull, McDavid, Ovechkin - the latter two with only one appearance so far) or who would rank even lower (Messier, Lafleur, Clarke, Sakic, Bossy, Trottier, Mikita, Fedorov, Kane, etc). Granted, Crosby gains some ground on many of these players when we adjust for the scoring environment, but the output is still fairly underwhelming.
Let's discuss each of his SCFs:
2008 - Hossa has 7 points, a 20 year old Crosby has 6 points (3 ES), both are plus 1. The Pens were up against a juggernaut Wings team that shut down everyone on the Pens, notably Malkin, who was playing injured. There wasn't much more to ask of Crosby in that series. His counterpart, Zetterberg also had 6 points (3 ES) and was a plus 1. Datsyuk also played the most against Crosby in that series.
Crosby not producing in that series was very low on the reasons why the Pens lost. Not sure even Malkin playing at his full capacity changes that result anyways. The Wings are the clear best post lockout Cup winner. Crosby still ends up as the youngest player ever to lead the playoffs in scoring.
A good comparison is a peak Lindros in '97 against another overwhelming Wings teams -3 points in 4 games or Wayne in '83 - 4 assist in 4 games. Crosby's losing SCF performance was better than those two, he got his team within a goal of going to a Game 7.
2009 - It is well understood that Crosby's point totals do not reflect the impact he had or the degree to which the Wings threw everything they had into shutting him down in the belief that their support players could outplay the Pens' support players. Zetterberg had one more ES point that series and Lidstrom notably had only 2 points after being above a PPG up to that point.
2016 - The 2016 Pens are in the mix for 2nd best Cup winner since the lockout and perhaps the 2nd best puck possession Cup winner behind the 2008 Wings. They were rolling three scoring lines lead by Crosby who has a career 3rd liner and an AHL callup who was terrible defensively on his line. They were able to spread their star players over three lines with a strategy to max out the offense of the HBK line against the other team's 3rd line and 2nd/3rd d-pairings. It was as important that Crosby's line scored as it was that the other team's # line didn't.
In the SCF, Crosby was great all around in Game 1 he set up the OT winner in Game 2, the Cup winning goal in Game 6 and the Cup clinching empty-netter. Meanwhile, the Sharks #1 underproduced.
No Pens player was above a PPG despite it being a dominant win by the Pens.
2017 - Crosby is the clear best player on the Pens and has the best SCF single game performance in Game 5 out the 25 SCF games the Pens played.
He is the best playoff performer of his era and a Cup resume befitting his status as a Top 5/10 player all-time. I don't think he loses any ground to any of his peers like Beliveau and Hull if one chooses to only look as SCFs, which is unfair given the different playoff formats anyways.
