Stamkos said a lot of things leaving the door open, and, I think I can say this now that it hasn't happened? A mod can tell me otherwise? Someone I personally have a lot of reason to believe told me he knew the family (told me that when he was in junior, originally) and he (not a Leaf fan btw) was sure he was coming. Stamkos was a special case, and they blew their chance. I'm not saying they'll never get Tavares, but it's not the same. There's no reason to get your hopes up two years out, and honestly, the only way I could see it at all is if the Isles fall apart the next two years, and the Leafs get really good, really fast.
Now, as for that... I think the Leafs are pretty good right now, tbh. They were a decent Corsi team last year with some bad luck, and I think the kids who will be up next year (and fwiw my guess is that it'll be Nylander, Marner, Matthews, Soshnikov, Rychel, Hyman, and Carrick, and if you wanna count him, Nikita Zaitsec) are all already really solid players. Sosh, Hyman, Rychel, and Carrick don't have like, massively high ceilings, but they're all also not 19 like the others. 21-23 for the lot of them. Should be expected to be players now. The other three are legitimate future top line guys, and I think they've all shown as much as they've been able to that they're ready to be players. They probably missed whatever opportunity they had to do like the Blackhawka/Penguins and win while they're on rookie deals by not getting Stamkos, but tbh the only two teams in the division that look really good are the Panthers and Lightning, and at least three teams have to make it, and I'm not a huge enough fan of the Metro teams to assume they have to make it (tho I think I'd take the Penguins, Capitals, Flyers, and Islanders over them, at least, and so to get the other WC they have to beat the Hurricanes, Devils, Rangers, and Blue Jackets - not a monstrous task imho but also not s given) via the division spot.
And the Isles? Well, they're a good team. They won a playoff round this year, they kind of underachieved in the regular season, but I sorta see how they played, like a fringey playoff team, as their floor. Sure, they lost some guys, but eh, Nielsen was getting older, and Ladd probably about makes up for Okposo for now (term will hurt, given Ladd is older), and they still haven't been giving ample opportunity to Ryan Strome, and they have Michael Dal Colle too, so to me they've got at least a few kids to fill in. They've drafted well enough that even if their top guys get older/leave, they can replace that value and stay competitive. In other words, I don't think we're approaching "Tavares wants out" territory.