Why not standardize a body in the GET request (which isn't forbidden per spec and works in many places already but isn't supported everywhere because it's not mandated to support it)?
Also, anyone using these servers is not currently putting params in GET body because doing so wouldn't work.
Those that oversee evolving standards seem to take extreme cautious to not rock the boat, and so more and more gotchas for the sake of backwards-compatibility keep getting added to the mountain of random details new devs have to learn. Which will soon include the difference between a GET and a QUERY I guess.