RT came out in the 80s so I'm willing to cut it a lot more slack than I would for more recent games.
Tbh, Neomunda would be the most appropriate of contemporary GW games to re-introduce the need of a gamemaster, as it's the closest in spirit to Inquisitor, the only GW game (that I know of) to explicitely require one. And, if memory serves, Oldmunda has been used as a test-bed for Inquisitor to an extent (in the post-Outlanders era). But that's not what they did.
I think its interesting how their are people on this forum who are really against GW overwriting everything, and creating a ruleset for every scenario, and yet other people (or sometimes the same) who take issue when GW afford players creative freedom to play the game their way - GW have made plenty of missteps with this game, but it seems that they also can't win with the 'fans'
They'd have to seriously ramp up their game, yes.
It's not GW's place to 'afford <me> creative freedom'. I don't need their blessing to come up with house-rules and what-nots. Any statement to that effect sounds empty at best. What they could do is actually come up with ways to enable said freedom (i.e. a
genuinely modular game).
Them churning out specific rules for everything actively reduces the design space left to the players. The more <official stuff> there is, the less <your stuff> you can have. Which wouldn't be so bad if the <official stuff> was actually well designed.
Imagine an elseworld where their bricks being able to actually stick together was such a secondary concern for LEGO that it would be impossible to assemble any of their kits, even when following the instruction to the letter. And when confronted with the issue, they would simply point out that people are free to ignore the instructions, carve their bricks with a knife and glue them together to build whatever they want. And then they would resume making even more bricks in even more weird shapes and colours. That's exactly how it feels GW is behaving to me.