The big two ideas on ranked-choice voting and non-partisan primaries, I
don't know how one would classify those as liberal or conservative.

These are policies usually put forward by Democrats. Progressive voting reform is liberal. Just look through all the places where RCV is used; nearly all major cities passed by Democrats: https://www.fairvote.org/where_is_ranked_choice_voting_used

What about data as a property right?

The closest thing to this being passed in the US would be the CCPA which was passed by a Democratic supermajority in California.

Or term limits?

I don't see anyone advocating for this, honestly.

Even the most objectively "left-wing" proposal, UBI, is not left-wing when you look at its history. The closest it ever got to passing was with the full support of President Richard Nixon in the early 1970s.

Yeah, I definitely think way more of FDR, Huey Long, and the like in the wake of the great depression rather than McGovern and Nixon's proposals (which occurred at the same time pretty much across both parties), but yeah populists of both stripes have historically done similar, sure.