It won't happen this term because Manchin and Sinema won't allow it.
If Democrats run on a court-packing platform in 2022, and get majorities in both houses, then it will happen.
However, those are both unlikely and it's even less likely that both happen.
The only way it happens is if the Roberts court hands down a decision that gets the Dems' base really fired up. Repealing Obamacare would do it. A decision allowing a state abortion ban to stand probably doesn't get there because it wouldn't affect most states and therefore wouldn't affect most women.
I think Roberts knows all this which is why he's punting on abortion until an opportune time and why he's never going to vote to repeal Obamacare. But Roberts isn't the swing vote anymore since RBG passed. So the question is, do any of Trump's 3 appointees see things the same way?

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