In 20 years, kids hearing the term "trumped up" might assume it's a reference to Donald Trump's reputation for lying.

Conversely, I can imagine a MAGA parent teaching their kid that "Trumped-up charges" refer to all the baseless charges those nasty lib DAs brought against him.

I'm sure there are adults right now who think the same thing.

That's very possible. This process is called "folk etymology", and your example of "playing the trump card" is folk etymology-induced semantic drift.

The rest of us already do now.

I'm still hoping that eventually the trump card in a hand will be the worst card you can get. So far it just helps you win for being lucky, except I guess that sort of fits for him too. Just shouldn't be a positive thing since he's a well of grievances, like festivus year round.

I won't correct them.