Logan: Nature made me a freak. Man made me a weapon. And God made it last too long.
Donald Pierce: Charles Xavier, the world famous mutant octogenarian.
Charles Xavier: Actually, I'm a nonagenarian.
Charles Xavier: I don't think Laura needs a reminder of life's impermanence.
Donald Pierce: Geez, Wolverine, seeing you like this, it just breaks my damn heart.
Logan: As soon as I rip it out of your chest, fucker.
Charles Xavier: Fuck off, Logan.
Logan: See, you know who I am.
Charles Xavier: I always know who you are, I just sometimes don't recognize you.
Charles Xavier: This is what life looks like: people love each other. You should take a moment.
Charles Xavier: Two days on the road, only one meal, and hardly any sleep. She's 11, I'm fucking 90.
Answer: Dr. Rice tells Logan the mutants have been wiped out due to a drug in the food and water supply that suppresses mutations, thus no new mutants had been born in 25 years. In the film series, it's indicated mutant powers usually come out during puberty, so parents don't know their children are mutants until around 12 or 13. So it took over a decade to realise no new mutants had been born. However, the government had been breeding mutants for weapons, which is where the mutant children come from in the Logan film. Furthermore, it is implied the "Westchester Incident" was an uncontrolled seizure of Charles Xavier that resulted in the death of many of the mutant students.
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