So I think you raise some good points but bear in mind my overarching premise in my comment: Nothing improves conditions that Republicans didn't already have in prior elections. Now, there is if anything diminishing returns across all vectors which tend to benefit the GOP. That being said:

Regarding COVID, I'm not referring too much these days but of the early post-vaccine era where last I tried to best calculate we saw a ratio of about 4 or 5 conservatives dying for every Democrat. Yes, it doesn't particularly impact an amount on a state-by-state basis, but the key point is: Did this help Republicans? Absolutely not; it has only hindered them. Does this matter in red states? Of course not. But in purple states and certain districts it could mean the difference of turning red or blue. We of course saw outcomes decided by literally a handful of votes. Considering this elderly Republican population most at risk is also a group that is most likely to turn out to vote for Republicans, then that hinders their most loyal base.

Yeah, right-wing rhetoric is heavily pushing an alternate reality that the economy is going to shit and everything is bad. Yeah it may stick to some people, but the reality is these words are largely hollow. Whether the economy is good or bad, it's true that there will be people who just find a reason to blame Biden because he's a Democrat. You can't stop that but you don't have to; for they were always going to vote Trump anyway. The key point is that these arguments -- permitted people like us raise our voice at dinner-tables and social media -- can be quickly dismissed because the data that Republicans normally tout negatively are pretty positive.

Look at what overturning Roe said. Even in an interview with a GOP Strategist I saw on PBS -- they said the Republicans had no idea that overturning Roe be this unpopular even amongst part of their own base. FWIW my mother-in-law is a lifelong Republican who even voted for Trump and because of this reversal of Roe and how protective she is of her kids, she is now vehemently anti-Republican. Basically, it took away the choice of her daughters and now she's pissed. Meanwhile it has been a major rallying cry for Democrats -- and 2022 again proved that. Religious voters will likely continue voting Republican, but that's largely a constant. If anything, they will feel less compelled to vote as they may feel their duty is done and they may get careless.

Don't get me wrong: I think polls should be some marker for concern and we should always assume the worst and hope for the best. However, and I say this again because literally nobody has remotely countered this point: The polls were deeply wrong for 2020 and especially 2022. One key facet of this was younger generations not sufficiently represented in polling.

I also agree that Biden isn't that great of a candidate. He's just -- dare I say -- the "lesser of two evils." Both candidates are old and largely useless; the only difference is that Biden isn't corrupt and his cabinet is full of competent experts. I'll vote for him, but you're right that he does not remotely inspire. If Republicans nominated anyone younger, Democrats would guaranteed be fucked.