Half the artists and the emulator developers didn't, though.
Yeah, it's pretty sad when even coders working on graphics stuff who should know better lack basic understanding of these topics. Don't even get me started with the proper use of gamma correction; 99% of the world (including most Adobe apps, various software libraries, image viewers, etc) are doing it absolutely wrong. E.g. most blending modes in Photoshop are gamma incorrect, but it can't really be changed because people are used to the broken stuff (you can fix it with plugins though and by not using about 90% of the blending modes).
Game devs have started to see the light in the last 5-10 years or so because you get horrible results with Physically Based Rendering if you fuck up the gamma, and of course any CGI & compositing software used in movie production got it right as far back as in the 90s because things go horribly wrong otherwise when dealing with real world footage... Most other people still live in the dark ages. Anyway, rant off...