well that’s a stupid title. this is just a beta design with no legit ties to any other pokemon
I’m not seeing a link. Missingno.'s sprite is just the graphics decompression routine attempting to parse data from elsewhere in the ROM due to a wrong pointer, this obviously can’t be concept art for that sprite. The idea that they might’ve considered making it canon in later generations is far too unlikely as well, we know they hated that this glitch got found and never ever ever would’ve wanted to acknowledge it.
The article’s conjecture is just “it’s blocky and it has writing on it, and if you squint really hard, you could pretend writing is like glitchy pixels.” Too much of a stretch.
It’s the latter if anything (a more recent canonization). And cut because that’s too weird, and not the interesting kind of weird.