The media will do what it has always done....it will switch to whatever president/party is in power and go after them at every opportunity....people have short memories, they went after Bill Clinton and the Dems without mercy over his sexcapades.... although Trump has set the bar considerably lower (underground) as to what constitutes bad/stupid behaviour so we will have to see how long it takes for the mainstream media to forget about Trump.... actually since Trump isn't really going away and will be telling anyone who listens that he will be the Republican candidate in 2024, the Dems may be looked upon with relief/favor for quite some time....
As for the Dems having their way in the 3 houses...I expect them to tear themselves apart at the seams with the progressives (regressives) fighting the moderates and getting very little of substance done, heck they may have to get moderate Republicans to work with them!!....just like the Reps in their first 2 years with Trump, they should have done a lot more but ended up fighting amongst themselves....