Likely have too much faith in the system, but I'm generally against changing the rules of the way the Supreme Court has operated since 1869. There have been times when the Court has been considered too liberal or too conservative, but everything runs in cycles. Also, while I detest the hypocrisy of the way the nomination process operated in 2016 versus 2020, it's not like Trump's two nominees Gorsuch and Kavanaugh are in lock step during their brief time on the Court; the fact is that both those guys are qualified for the Court, and don't think they will follow a strict conservative line. They have already disagreed on opinions. Even with Amy Coney Barrett and her weird People of Praise background, I'm not convinced that the Supreme Court will be as much of a problem if Biden is elected and Dems control the Senate (which is an assumption that may not be realized).
Finally, if the Dems take the step of changing the structure of the Court, that further opens pandora's box for future changes when control shifts back.
All of that said, I'm not concerned about packing the court or changing the rules for the Judge's tenures right now, and agree with Biden's position to not address the issue for now. Let's get Trump out; take as many seats as we can in Senate, and then assess.