Count me in as one of 3D TV's few fans.
We bought our current TV a few years back (2012 or 2013 IIRC). We weren't specifically aiming to get a 3D (or even Smart) TV, however we lucked into a Cyber Monday deal that had a Sony KDL-46EX720 TV with a Sony 3D BluRay player for $750 (CDN) -- only one of three being offered in all of Western Canada. We scooped it up -- and for the most part it has been an excellent TV.
A year or so later we were able to pickup two pairs of 3D glasses while in the US (where they were half the price we could buy them in Canada for). I dove into as much 3D content as I could. Sony had at the time a great Internet "channel" in its Internet Video section which features all 3D videos, most of which were of UNESCO World Heritage sites. They were short, but those were great to watch. I'd watch 3D YouTube as well from time to time, and of course I own a bunch of 3D BluRay movies.
Unfortunately, first they shut down their 3D online channel, and then they decided not to update the set when YouTube changed its API (as I had predicted when we bought the TV, the "Smart" features wouldn't last all that long. As I said, I wasn't looking for a Smart TV. We don't use the Smart features at all anymore in favour of using our PS4 or Apple TV instead). There was never any regular 3D TV content available here in Western Canada (i.e.: no 3D broadcasts on cable or antenna), so the choice was between short Internet clips, or full blown movies.
I unfortunately missed the PS3 era; 3D doesn't work over PS Now, and there have been only a handful of 3D TV enabled games on the PS4. That was one area where 3D TV would have really shined; I regret never having had the opportunity to play ICO and Shadow of the Colossus in 3D.
My wife never got into the 3D viewing, so I'm the only one in the house who ever uses it. About the only time I get to use it is when I'm home alone, or after everyone else has gone to bed. Still, I did get Star Wars VII on 3D BluRay when it was released back in November, and have been enjoying watching it again in glorious 3D. I'll probably still buy our movies in 3D BluRay packs while I can (the 3D packs generally also come with the 2D BluRay, a 2D DVD, and a digital download copy, so they can be a really good deal), and will probably have to keep our current TV somewhere in the house for as long as it continues to function to watch them. Ultimately what did 3D TV in was the lack of content (particularly TV shows in the 30 mins - 1 hr range), the cost of the glasses (the TVs should have come with two pairs each, and not sold them as $100 each add-ons!), and general apathy towards wearing the glasses. Oh well -- it was fun while it lasted.