I think they could pull it off if they wanted to but i think everyone loves them for there GTA games. GTA5 looks amazing i hope they have gone all out on this one.
A futuristic sci-fi open world rockstar game would be good, but just don't make it under the GTA name, it would have to be it's own separate series. Calling a sci-fi game a GTA game would be like calling Red Dead a GTA game, it's just not right. GTA is about life in the modern criminal underworld, not science fiction, or western or anything else, its a modern crime game, science fiction open world would NOT be what Grand Theft Auto is about. IDK though, just my opinion.
I think it's a great idea, like he said, if done right. Look at Red Dead Redemption. It was like a GTA but in a western era and turned out to be amazing. If they do this it would be a fresh start instead of the same 21st century stuff.
Houser's response is actually the opposite of 'very tempting'. He doesn't seem to think it's a good idea but is being nice in entertaining the person that asked this uninspired question
I did read somewhere that they might be doing a new bully for PS4 or considering the idea.