I get what you're saying, but I think that's a rather terrible way to contrast radioplays and content made for TV. The experience of watching "Game of Thrones" isn't that different from listening to the BBC radioplay of "Lord of the Rings"[r]. I think "The Wire" or "Generation Kill" might be better examples of things that I think work better on TV, than I can imagine them doing on the radio. Or maybe "The Expanse" or even "Firefly".
Doesn't mean I don't like "Game of Thrones", I love the adaptation - but with its many characters and demanding storyline (even for those of us that have read the books) - I don't know. Somehow, while it is a beautiful production, I think it could've worked with a similar script for radio.
[l] Apparently the original series, in its 13 episode format isn't available to download/buy - if I understand it correctly the following Amazon link is to the remaster: https://www.amazon.com/Lord-Rings-Fellowship-Ring-Dramatised... See also: https://en.wikipedia.org/wiki/The_Lord_of_the_Rings_%281981_...
A search did turn up this: https://soundcloud.com/inkmore/sets/lord-of-the-rings-radio
Which I assume should probably be taken down due to copyright infringement.