I have to retract my 80% number, because I forgot about Paizo until you mentioned them. I forgot that for the last couple years (until recently) I had a subscription to their adventure paths, which throws off my accounting of purchases by quite a lot. (and I forgot because they were largely going straight to my shelves and not being run ... which is why I eventually cancelled my subscription)
The reason my 80% was pretty much correct without that, wasn't about smaller publishers, it was about almost exclusively buying PDFs anymore. It was that "except for special things" part -- first print run of D&D 5e, because at time I didn't think I could get 5e PDFs from WOTC (I don't recall if they changed that policy, I hadn't been looking at them for a while before 5e came out, nor since 5e first came out). I know they're doing a lot of older editions in PDF lately, been buying those up a lot ... but for 5e, I don't recall if they're still print-only or not. I didn't catch the 5e bug, so I haven't paid attention.
With Modiphius: I bought physical prints of the new edition of Mutant Chronicles, not to use them, but to collect them (my favorite setting ever, so I backed the kickstarter at almost the highest pledge level -- which got me _everything_ except miniatures). When it comes to _using_ Modiphius products, it's all about PDFs ... I only buy their physical prints as "special things" -- nostalgia on my bookshelf, not use. And, to continue on your list: I haven't ever bought anything physical from Pelgrane or Cubicle 7, and it's been since the 1990's that I bought physical products from Chaosium (I do still buy PDFs from you guys, I promise ... but I took a hiatus from gaming somewhere in there, and when I started buying Chaosium stuff again, it has been all PDF, and pretty much through DTRPG... kinda miffed that the Guide to Glorantha PDF isn't on DTRPG, even though the Atlas is).
(and if you brought Ringworld back, especially as a general Known Space product instead of focused just on the ring, I would absolutely buy that as a physical product... might even put in a large bid on a kickstarter for it; but I wouldn't be surprised I'm almost the ONLY customer you could count on for that).
For the last half-dozen to dozen or so years, I've been a PDF gamer, not a printed book gamer. Doesn't matter if they're a big publisher or a small one. Paizo's adventure path subscription was the only significant exception to that. (and I don't recall why I bought the physical copies for that; it wasn't a meaningful exception as far as I can recall) The other exceptions have pretty much been POD.
The only other physical print books I can recall buying in the last 5 years, that weren't POD or used/vintage-from-days-past, were ... actually, coincidentally, at Pacificon (or was it Dundracon?) a few years ago, Chaosium and Crafty Games were across the aisle from each other in the dealers room, and they had a great deal on print+PDF for their new (at the time) Fantasy Craft game. And I didn't see anything at Chaosium that I either didn't already own, or really wanted/needed. So I bought their deal for Fantasy Craft :-}
I generally look at printed books, these days, as "collectable for my bookshelf", "if I can't get it any other format", or "a side benefit to getting something else from a higher pledge level in a kickstarter". And those last two seem to be leaning a lot more toward POD, in my experience, lately. Either old things being reprinted via POD, or (as you suggested) small publisher KS's that deliver printed content via a coupon for a POD.