@Peter of Leaky Paywall asserts:It works for the NYTimes ...

Does it? Do we know that? Is NYT sharing their data? They do it, yeah, but that doesn't tell us it "works".

And really, is it useful or relevant, to compare eg WPTavern, to the NYT?

It's a tough climb-down, to put up a paywall, notice that it achieves nothing, or is counterproductive, and then take it down. "Well, that was a stupid idea". We've seen a few commercial sites do this ... try it for a year or few, and then shrug and go back to normal ... and we wonder about the others.

Like Jeffro, my honest first-reaction to the paywall tactic is not an upper. But again, maybe my bias isn't the whole & only story.

Certainly, for people who might not really be the NYT, some careful research, consultation and planning would be in order, before giving the paywall idea a try. It's definitely not a free gambit, like changing site-colors or font-spacing. There are intangible costs & affects involved, for the site operators, the clientele, and marketplace.