Every game is repetitive, it comes down to whether the repetition is entertaining. It wasn’t for you but for a lot of people it is. It is trending downward according to Steam stats but it still has around 60-70k concurrent players during the low points and in terms of hours played it’s be in the top 10 games.
Personally while the overall mission structure is “repetitive” I think the randomization of mission parameters, how the mission play out and the spectacle make it very fun. I would still be playing if not for the Sony shit. It’s a great game to peace out with friends.