Sure, but there are "get your kid to eat veggies" levels of "effectively impossible", and then there's "quantum teleport into the bank vault" levels of it.

This is more like the latter. There aren't many signs of us hitting the bottom thus far.

The ONLY time a sitting POTUS has been politically removed from power by the mechanism of impeachment, or even seriously handicapped by it, was after the GOP constituency began howling at their congresspeople about the egregious behavior of the POTUS. They resisted caring up until that moment, and that was 50 years ago.

The current GOP doesn't flinch when their candidate is found guilty of SA, with a long history of fraud and embezzlement. If Trump approved a simple burglary of a Democrat's office, it would barely make the news at this point.

Not all infinitessimals are equal, just as not all infinities are equal.

Even if it were possible for Dems to get control of the house and impeach the prez, there is no way that Senate will convict unless the GOP Senate goes back to becoming the GOP instead of the MAGA-GOP, which seems extremely unlikely.

A few million to Fusion GPS would be a good start

Unfortunately I don't see a route where Republicans vote for impeachment, ever. They're already refusing to listen to constituents, hiding from their elected duties and letting Trump freely crash the economy on a whim.

Not at this time, and I don't see it changing enough in 3 years to make any difference. The fear of being attacked by MAGA is still very high, I think the (older) republican leadership has decided to just wait this out.