If he's acquitted with no witnesses, he'll lose some vote 2020 votes, because it'll be seen as a corrupt sham.
If he's acquitted with damaging witnesses, he'll lose a lot of 2020 votes.
If you think Trump getting acquitted is somehow a win for him, you have zero understanding of how any of this works - and you should stop spewing harmful fatalism until you learn.
The fatalists said Trump would never be impeached. He was impeached.
The fatalists said Trump would use war with Iran to get magically reelected. He couldn't pull off a war.