Okay, Obama didn't have the benefit of future knowledge that Roe v Wade would be struck down. It was a precedent that had stood the test of time across decades.
Why the Dems didn't do it for the very short time they had both chambers under Biden, I don't know. Perhaps they had a naive belief that Conservatives wouldn't be the trolls they are.
But even if we assume they won't do anything about it again, which I seriously doubt based on how popular abortion access has become—even if we assume that, abortion isn't the only thing on the ballot, and people are voting en masse for the Democrats, because LGBTQ rights, environmental protections, and even American democracy itself is at stake.
To cast aspersions and wring hands over abortion when we're 30 days away from the election...I just don't get how that helps anyone. The die has been cast. Holding onto some vain hope that neither Democrats nor Republicans will win (or worse, that everything will burn down in some bloody revolution) is madness.