seems to me that the left will be getting their way for the next 4 years
Possibly, just two, even if Biden is declared the winner of the 2020 Presidential elections.
If the Republicans hold the Senate majority now, and possibly gain a seat or two in the 2022 midterms with the ~34 being up for re/election while gaining the majority in Congress as they have made waves in 2020 there, bills could fly through to Biden.
Now, the only thing that can be done here is a presidential veto from Biden. Then, it would go back to the Senate and Congress requiring 2/3rds vote from each to pass, which could be unachievable. However, if both Senate and Congress are working for the people, a veto would be very unpopular for the reelection of a sitting Democrat Senator or Congressperson and even another Democrat president in 2024 as they are going against the will of the majority that they are representing in those bills.
I'd like to see how Biden would spin a veto to make it so unpopular where they couldn't sway moderate Democrats, essentially fracturing the party, to get the 2/3rds needed to override Biden and get things done.
Otherwise, it's a stalemate for the remaining 2 years until 2024, wherein a Republican ought to win with a sweep of everything as nothing could possibly get done and there will be angry people on both sides of the aisle.