“Yuuri is canonically the jealous type.” No he’s not. Yuuri has shown maturity over situations where there might be jealousy involved. Literally the only time Yuuri could be seen at all showing what could be seen as jealousy is the ‘look at me!’ scene in Yuri on Stage in which he’s drunk and pouty and just being silly. It’s a small, cutesy moment.
This isn’t to say that Yuuri can never feel pangs of jealousy. Both he and Victor can. It’s a normal human emotion, and it happens. But he doesn’t let it overwhelm him and it doesn’t become intense enough to be a thing.
Jealousy plots aren’t cute, neither are plots where a character is overly possessive, and Victuuri wonderfully avoided that despite the fact that it would be an easy trap to fall into (especially with Yuuri considering he already thinks less of himself, and people are shown to think Yuuri is ‘unworthy of Victor’s time’, which of course they are wrong about). There’s no reason to insert them into canon where they don’t exist, let alone insist that it’s ‘canon’.