The obvious reason is that Leaf fans seem to have the biggest issue with Barzal succeeding in the NHL. That people would dare put him on the same level on almighty Matthews, despite Barzal's rookie season being the best since Malkin over a decade ago.
The Edmonton Oilers had a chance to draft him but traded the pick, plus a high 2nd rounder, for godawful Griffin Reinhart. Plenty of shots are made at their expense every time Barzal hits a new milestone- check the 80-point thread on the main board. They have every reason to express sour grapes about Barzal succeeding, yet you never see them in these types of threads posting condescending predictions about how Barzal is only putting up points because of this or that, or they can't wait to see how much he'll regress when Tavares leaves lololol.
Maybe it's because everyone knows Edmonton's #1C is still on another tier entirely than Barzal because when I say 82+ at 20, you say 103 at 21. I'm sure Toronto fans would love to say 103 to counter 82+, but that's not statistically possible, so it's 69+intangibles >>> 82+.