I think Obama's personal politics were actually much more progressive than those of Biden. It's just that his theory of governance seemed to revolve around taking the positions of moderate Republicans and then starting with those as his own position. He thought that would be taken as a meaningful step towards compromise and give him partners across the aisle.
Instead, that meant that the old moderate position became the new left position, and his opponents could move even further to the right.
At least he unintentionally provided progressives with a lesson on how not to advocate for policies going forward.
Mostly being facetious. However, it was nice having a president who could complete a coherent sentence. It's been nearly eight years since we've had that.