If the point is a multi-tasking sandbox, not heavy/sustained data-crunching, those old CPU's w/ boosting turned off or a mild underclock/undervolt (or an L spec which comes iwth that out of the box) really aren't any more power hungry than a newer Ryzen unless you intend on running whatever you buy at high load for long times. Yeah, on paper it still could be a double digit percentage difference, but in reality we're talking a difference of 10W or 20W if you're not running stuff above 50% load for sustained periods.

Again, lots of variables there and it really depends on how heavily you intend to use/rely on that sandbox as to what's the better play. Regional pricing also comes into it.