if you elect biden in 2020, he's going to pick a youngish female vp, and the assumption is that she's going to be in power within 2-3 years. so, you're essentially allowing biden to pick the 2024 candidate for you, which turns him into the lamest duck of all time. a biden administration will almost instantly transition to the vp; he'll have six months to take a few trips, and that's it. further, we're going to know who that is fairly soon.
a key question that those on the american left need to ponder is whether it makes more sense to accept the candidate biden is presenting to them, or whether they are better off waiting and trying to pick a new candidate in 2024.
you should expect almost nothing from biden's presidency itself, at all.