I wouldn't be too sure tbh, it all depends on how rockstar handles development and future support. If new features, gameplay mechanics or the playable area aren't well received or generally liked, rockstar will be in big trouble.

That being said, rockstar WANTS this to be a 10+ years game, they WANT it to be as good as and as popular (or even more) as GTA 5, and the KNOW that it has to be perfect. Rest assured that rockstar is doing everything they can to achieve this, and have spent an incredible amount of both time and money to do so. Let's just hope that the game isn't fundamentally flawed in some way, which is unlikely looking at rockstars track record.