I agree on this take. I would be curious where the maximum playoff teams vs. season relevancy line is, though. For example, i think we'd all agree that a 7 round, 128-team playoff would be ridiculous, an I only include it here as an obvious "that's too much" line.
I think the key question is "how many teams still have a legit shot of winning it all"? If that answer is around 20, then there needs to be space for around 20-ish teams to make it; less than 20, really (16 falls within that range). Then, regular season becomes important. If only 4 teams have a legit shot to win it, then a 16-team playoff system is too much.
As it stands right now, there are likely 20+ teams that have a real shot of being good enough to compete for a championship (possibly more). 16-team playoffs sounds good. I'm happy with the 12, but I'd be happy with 16.