@ajp  When the IRS shuts down MeF, typically, neither current nor prior year returns can be e-filed until the system reopens.

You can now e-file business returns because MeF for business returns was reopened on Jan 8, 2021 as announced by the IRS.  At the time that announcement was made, there's no update yet on MeF for individual returns.

The IRS then made an announcement last Friday (to the surprise of those who were betting that MeF for individual returns would reopen by late Jan as in prior years although it is not totally unexpected given the circumstances) that MeF for individual returns will only be reopened on Feb 12, 2021.

So, there you have it.  If you want to paper-file 2020 individual returns before Feb 12, of course you could but I don't see how given the number of forms and schedules that are still in draft.