Those players might not get the years, but I would think they'd see the AAV
I mean, this is a huge caveat, and it makes the statement worthless.
You're ignoring that the exact reason teams won't want to give Bryce Harper 12/$400 million is because he might be worthless or a platoon player by age-33, and they'd still be on the hook for 4/$150 million.
It's silly to talk about Mike Trout, who is projected for 9.2 WAR next year (Bryce is projected for 4.9). He's A-Rod and Harper is Stanton.
But yeah, if you want to say a lot of teams would give a lot of 26-year old hitters 8/$280 or so, I agree with you. But no one is jumping to give 1 or 2, let alone 3 or 4, extra years for what teams probably discount to almost worthless.
Look at the best 25 or under hitters from a decade ago. Basically the only who would be anywhere close to a huge 3/4 year contract would be Joey Votto. Almost everyone else is a bargain basement signing or on a contract their team regrets.