I think: maybe a little less farfetched then he does, especially under a President Biden who knows the Senate best and how to work it.

When I just posted this retweet by Michael Steele, a former head of the RNC, of The Lincoln Project (former Republicans who have not joined the Dem party) targeting the Trump sellout Senators. They aren't going to stop as long as Trumpism is a factor, they're angry at what their party became under Trump:

And how supportive the people of Utah are of Romney and how he has complained about how Mitch McConnell's Senate gets nothing done.

as well as a reminder of things he's done like marching in a BLM protest and how Obamacare is really just a version of Romneycare.

When I see that the people of Maine are even more supportive of the independent ways of their Senator Collins no matter how much she is ridiculed:

When I see articles like this

And suggestions that Biden is one of the few Democrats that Mitch respects:

not to mention Mitch saying this.

When  the conservative Cato Institute also agitates against Trumpism

When the neo-cons of The Bulwark are anti-Trumpism as well.

When a Republican governor is saying on TV that Trumpism is bad for The Republican Party

When I see the fatalism of liberals bemoaning how the obstructionism, it's always gonna be how it was during the Obama administration (and some even argue it was like that during the Bill Clinton administration, which I don't buy if you are talking about before the impeachment)

AS IF NOTHING CAN POSSIBLY EVER CHANGE and things are always going to be the same forever--

WHEN TRUMPISM ITSELF MAY HAVE BEEN ONE OF THE MOST RADICAL CHANGES OUR COUNTRY EVER WENT THROUGH

How can you believe things can't change when you've just lived through the most radical change of most lifetimes?

Political scientist pointing out that winning GOP races for the House performed better than Trump, reads it as Trump populism not preferred by those type of districts:

Edit to add: there's some interesting replies to his tweet, both agreeing and disagreeing with how he's reading the phenomenon

here's a major problem, maybe THE major problem:

Donald Trump lost the presidency, but showed Republicans a way to win the culture wars with working-class Hispanics.

Despite four years of being defined as a racist for his rhetoric and harsh immigration policies, Trump improved his margins in 78 of the nation’s 100 majority-Hispanic counties. And he did better with Latinos in exit polls of each of the top 10 battleground states, a POLITICO review of election data found [....]

from Politico Culture wars fuel Trump’s blue-collar Latino gains

In the past, there was the tendency to attribute this whole thing to a white working class that is dying off. BUT it's not, because it also includes lots of Hispanics and they are growing, not dying off!

Then go for a minute with the simplified classic view of the original intent of the Senate and the House. Where the House is supposed to be the big messy unruly populist body and the Senate is supposed to be the elite grownups checking the populist fervor.

We currently have a significant noisy minority of Senators on the right side of the aisle who don't fill the role of elite grownups that they are supposed to and stoke populist culture wars, i.e. the Rubio types. All you have to do is form a majority block of the grownup Senators to counteract their demagogic populist culture war crap which should stay in the House where it belongs. Dis them to take their role as Senators seriously or run for the House instead.

this reminds me of how we've always had examples of happy bi-partisanship amongst members of different parties, especially in flyover but it always seems it only happens once they are no longer running for office:

Nate Silver said: That doesn't mean he'd ever in a million years vote with the Democrats on, say, taxes. But on basic good-governance stuff—letting Biden appoint a cabinet, protecting against future elections from being stolen—he would.

Is pretty much same thing here, now that he sees Trump out of the way: