alt Hacker NewsPolls for the last few decades haven't really been all that accurate or good ("it's 50/50" - worthless).
You also seem to be ignoring all the systematic changes that have been made during Trump 2 in your prediction for such huge wins for the democrats. Things like the final destruction of the Voting Rights Act and the extreme Gerrymandering have gone mostly towards republicans. Also 32% of voters (or more) still don't really see a distinction against Donald Trump and The Almighty. Forgive me but I'm not convinced it'll be the bloodbath you think it's going to be. Democrats might have a minor edge in the house when all is said and done and literally nothing else to show for it.
Gerrymandering can help Republicans in the lower chamber† but it can't help in the Senate where they're most scared. Every voter in Texas gets to decide whether to pick Ken Paxton or James Talarico and perhaps more importantly if they can't stomach voting for somebody with a D next to their name, they can decide they were too busy that day to go vote at all so it's not really their fault.
† But it might not, if you turn five 7/3 R seats and two 9/1 D seats into six 6/4 and one 9/1 you risk a dummymander where too many of "your" voters vote the "wrong" way and you have seven Democrats elected even though you still took almost 50% of the vote in some districts and you drew the maps.
Now the trouble is that voters seem to be imagining that if the Democrats take the Legislature that's the whole ball of wax and it just isn't. If there's a narrow D majority in both parts of Congress you can expect that to stall the stupidest stuff from Trump which was subject to congressional oversight, but the useless "We need bipartisanship" mewling will start almost immediately from people who apparently were 100% fine with party-line Republican decisions or executive override.