Sure, it's popular in one country, that doesn't mske it mainstream. Fortnite or Minecraft are mainstream games. There's no RTS that's even close to the popularity of those games.
That's not how this works, GPUs are fast because the kind of work they do is embarrassingly parallel and they have hundreds of cores. Loading a json file is not something that can be trivially parallelized. Also, zed use the gpu for rendering, not reading files.
Probably a side effect of our hyper connected world. It might have happened at the same rate in the past and you didn't know about it. It's also a case of people copying other people they see online.
Damn, you're right, it's almost been a decade already. I honestly thought it was younger than that.