If he's not set on a destination, and he's not re-signing with the Leafs, how would he come with an extension in a trade? These made up scenarios make 0 sense
He has a NMC kicking in on July 1st.
He literally has an "exit if I feel like it, and you can't trade me unless I agree" deal that kicks in on July 1st.
Matthews has a ton of power with his next contract/destination, assuming he refuses to extend or be moved.
His agent could say even if traded before July 1st, he has no intention of considering signing with the team he's traded to until he has to.
It could be a bad situation, and the Leafs need to get the most they can.
But maybe they get the extension, or maybe they call his bluff and he extends, or he totally screws the Leafs and that is totally his right to do that. We can't read his mind.
Same scenario as Tavares. He doesn't owe anyone anything. Just like us, we will (if we're smart) put ourselves into the best situation we can as far as employment. The loyalty thing is a personal choice.