Just How Old Is William Stryker?
William Stryker is the self-serious asshole who leads the Weapon X program, which created both Wolverine and Less-Good Deadpool. He's the main villain in X2, storming Xavier's school and being played by a surprisingly spry Brain Cox. And I say "surprisingly" not because Brian Cox isn't a nimble theater imp, but because his character is old as hell. See, in Origins, which mostly takes place in 1979, he's played by a 47-year-old Danny Huston. This would make him, fuck, somewhere in his 70s in X2.
But then again, in Days Of Future Past, where the past past (as opposed to the future past) is 1973, Stryker is played by Josh Helman, who was in his late 20s at the time. So that would put him in his 50s around X2. That's a 20-year difference, and while to younger people, both ages probably seem amazingly, unknowably old, the body does A LOT of dying between 55 and 75.
Why Was The Cure From The Last Stand So Useless?
A big plot point in The Last Stand is that there's now a cure for the mutant gene. You can get an injection, and suddenly your blue fur is gone! But it turns out the effects are temporary, which kind of defeats the whole point. Rogue gets the cure, but in the future (past) section of Days Of Future Past, which happens in the same timeline, she has her powers back.