Biden has been Trump 2.0 so it's clear why Republicans would say he's been okay or good. It's not so clear why Democrats would, though. Biden literally has zero substantive domestic legislative achievements. Oh sure, that's been baked in ever since he failed to win any working majority on November 3, 2020, but why should that count in his favor? He was at the top of the ticket, so he has to take responsibility for failing to bring downballot Dems across the finish line.
Obama had filibuster-proof majorities (or close to, anyway) in his first two years and his one substantive accomplishment was a deeply flawed health care reform bill. Also, Biden’s NLRB appointments are a massive improvement over recent Presidents of both parties. Not to mention, reopening the country after the pandemic.
And while he was at the top of the ticket in 2020, at least Biden was better than most of his party in terms of avoiding the nuttier parts of the BLM movement and the Left in general, which hurt Democrats downballot and made Biden’s election closer than it should have been.
I don’t think Biden’s been a particularly good president on either foreign or domestic policy overall, but then again, the bar is incredibly low and so compared to many of his predecessors he looks better—especially if you put aside charisma and ability to charm/interest the political media.