I did not say that either player was finnicky. Both players are as capable of raising the game of their linemates as pretty much any stars I have watched over my lifetime. But it has always been the case that it is not easy to play with great players and succeed individually. Playing with a guy like McDavid requires you to do certain things at speed that you may not be comfortable with. Crosby is kind of the opposite. He is at heart a grinder and his game suits certain types of players that fit that style.
You need to focus on what really matters and that is the success of the team. Sometimes a pairing can turn one player into a complementary player but the impact on the team is still positive. A while back I posted about Nuge with McDavid. Nuge's IPP away form star players is generally over 70% often in the 75%+ range. With McDavid over three years it was 55% and in some years was under 50%. Yet if you look at what happens on the ice you see that if you pair Nuge with either McDavid or with Leon but not the other the teams GF% rises as opposed to the player by themselves.
That means the team is more successful even if Nuge's tendency to play more passive impacts his own numbers to a degree.
Now lets look specifically at the bolded claim: Here is the data 5 vs 5 for the Penguins in the three years from 2015-2016 through 2017-2018.
https://www.naturalstattrick.com/li...ict=incl&p1=8471675&p2=8471215&p3=0&p4=0&p5=0
With Crosby on the ice but not Malkin the Pens scored at a rate of 2.92 g/60 and with Malkin but not Crosby it was 3.09. With neither on it was 2.10 g/60. The GF% were respectively 55.31, 56.00 and 48.76.
When both were together in 58 minutes the Pens did not score. Malkin and Crosby don't work together 5 vs 5. They never have. Their games are just too different. Malkin plays like Draisaitl does when he is away from McDavid.
Here are the numbers for McDavid and Draisaitl over the last three years:
With Connor but not Leon ----- 3.43 g/60 GF% 57.85
With Leon but not Connor ------3.08 g/60 GF% 52.63
With neither on the ice --------- 2.26 g/60 GF% 48.64
Now together that number jumps to 4.25 g/60 which is insane. It works because Draisaitl has adapted his game when playing with McDavid to be an almost perfect complement, just as Kurri did playing with Gretzky. This is why I think people underrate Leon. They think he is a product of McDavid but in reality it is his incredible ability to morph his game to fit McDavid that makes the pair together so dynamic.
In the end, I don't see any evidence supporting the assertion that the Penguin combination was better driving offense apart, in fact it is probably the opposite. The GF% with Malkin on the ice but not Crosby was a bit higher than Leon without McDavid but during that period Draisaitl did not really have any steady linemate, while Malkin had Kessel and when those two played together the GF% was 58.78. Leon had a lot of his time over that period playing with guys like Yamamoto.