Well I have no problem with repetition of a genre, to a reasonable limit, and I LOVE homages. It’s the recycling of far more specific things, and total lack of original IP, that I disdain. Reading your list of movie-show-show-movies just made me puke a little bit in my mouth. (Incredible quick compilation there though, nice). I am however glad you left out the TETRIS movie. Wait not movie… trilogy. Yep, I said it. Now the less attention we bring to it the better. (Ugh, where’s my Pepto-Bismol?)
Now the Spags you mentioned weren’t remakes or adapted material, especially in the sense we’re discussing. So I am not really getting the correlation. My contempt is with remakes,reboots and ridiculous franchise greenlights (Battleship? FML) although I will derail into overall quality a bit since you’ve nudged. 
Moments like Sartana stepping onto a blowing desert stage, turning slowly, eyes peering through the shadow of his brim, delivering a helluva line, unleashing a bevvy of insane weaponry and skill with those surreal gunshots distorting your speakers, etc, etc… these sorts of moments are never cultivated in these tired franchise bloodlettings. Instead we seem to get rushed productions, slap a dude on a green screen, read the dialog from the screenplay written by the same “it” guy who wrote the last 20 screenplays of the same genre and perform the same action that got the other show-movie in the sound-stage next door an Emmy/Oscar. Rinse repeat. I can just smell the profiteering emanating and see the quality and attention to detail dissipating. Its sort of a gloomy new world in general for entertainment, but piggybacking off existing IP just takes it down a whole 'nother peg for me.
If you change everything, repackage it for a modern audience, swap genders and races of iconic characters, slam it in different settings and on and on and on then why not just reflect this complete departure in the nomenclature as well? I would. I mean you’ve already done so much work to make sure there is no trace of the heart and soul of the original, why not? Unless of course… the obvious, blech.
I think the Marvel stuff is working for two reasons. One, the freedoms of the Netflix production schedule/executives allows them to write and shoot with meticulous care and value. Secondly, it is not cannibalizing an old film or TV program (or title), quite to the contrary it’s realizing existing material into the moving picture medium for the first time… and actually respecting the source material. This is an important distinction, and at the very least should be judged a such.
As far as organizing search parties for expeditions into TV land in quest of the holy grail… well I just don’t have that kind of time, can’t afford to gamble that much. The ROI is negligible as you’ve described. Now if something jumps across my screen that was directly born of a writer/director/creators personal thoughts and dreams then I kill myself to make the time, this really excites me, inspires me. I can watch a trailer and smell crap within the first 30 seconds, weirdly Rotten Tomatoes typically concurs. I’m big on first impressions and have a full plate when it comes to my downtime, so I have to be super selective, and it’s almost always a return to yesteryear for me. Notably more so in the last decade. How much of this is age and nostalgia vs. bonafide quality of and pride in one’s work? Well… I know which way I lean. There are a couple here and there, I agree, but man that ROI. This, among more obvious reasons, is why I turn to independent film so much, it’s the last vestige of auteurism and new concepts. I truly believe/experience that.
I try to never sell that old adage “They don’t make 'em like they used to” short, or whisk it away under a rug of things old curmudgeons say… because if I do that then I feel I am taking away from the real blood sweat and tears that these creative giants and master craftsmen poured into those works of art.
p.s.
Aren’t we way over do for another WIZARD OF OZ adaptation? I mean come on it’s been like a few months already right? facepalm