I'm more surprised at PewDiePie, tbh. Jason runs a Mastodon instance, with the account notjustbikes@notjustbikes.com (I'm hoping that by leaving out the @ sign before the local username, that won't send him an unwanted notification), so the fact that he's also a Linux user is less surprising. I don't watch PDP, but I gather he has a very large and impressionable audience, so him promoting Linux should be good!