I was thinking a bit about this and how the Rs should handle it, given that they're not going to stop an appointment.
The "vengeance" part of me wants to see the appointee Kavanaughed just so the Ds can get a taste of their own medicine (of course I know how the MSM will twist it given that it's not happening to a white guy). If the appointee is someone like Ifill, who is a dream candidate for the squad, that could be appropriate though.
Otherwise, if it's someone like Brown-Jackson, who seems to be rising to the top and also looks to have the creds, even if they are very liberal, it would be interesting to see the Rs say, "ok by us", or even "good choice", not lift a finger to stop it, and that's that. Sure, it could cause an MSM orgasm of "Biden won!", but it could also cause a lot of far left heads to explode trying to figure out why the Rs didn't fight it.
If this were an appointee to fill a 4-4 vacancy during the last year of a lame duck presidency, I might call for a different strategy. In a one to one swap given the current makeup, not being total whackos like the Ds were during Kavanaugh could be a good strategy.