The Democratic majority in the Senate is admittedly the narrowest possible. Still, it should enable Biden’s Cabinet nominees and his judicial nominees to to be confirmed without undue stress, and it at least renders real legislation somewhat possible - starting with those $2,000 COVID-19 stimulus checks which the Republicans prevented from passing (a foolhardy decision which may have helped cost them those Georgia seats) And should there be another Supreme Court vacancy in the next two years, it will be filed with someone other than a Federalist Society hack. More ambitious things may be harder to accomplish, but it is at least possible that the continuing crisis in health care access may be effectively addressed. Deeper, structural reforms like admitting new states to the Union and eliminating the tyranny of the filibuster may be harder to accomplish, but they should at least be on the table.
There is the danger, of course, that the Democratic majority will fritter away its opportunities in the short interval before the next election on investigations and culturally divisive "identity" politics. The fact is that, to the extent that voters have empowered the Democrats to do something, they have done so in the hope that they will actually do something at last - do something that will actually improve people's lives, everything from short-term remedies like covid checks to longer-term reforms. Maybe Medicare for All may be out of reach, but Medicare for a lot more people may not be. A public option may be out of reach, but more expanded Medicaid for more people may be achievable. The point is that there is so much that is wrong right now that even moderate reforms may significantly improve people's lives - and get a Democratic Congress reelected in 2022.
The reckoning with Trumpism will remain a priority, and Trumpism will still be a force to be reckoned with whether Trump is running in 2024 or Trump was removed a few days before the end of his term and disqualified from running again. But the most effective and long-standing recking with Trumpism would be for the Democrats to use their control of congress wisely and well to offer an alternative attractive enough to keep the Republicans out of power for a long time to come.