i. Most of the open world games are just games pretending to have a lot of content by making a huge and boring world, throwing in a huge number of boring collectibles, boring side-missions and boring times where you have to go from point A to point B. There are rare games that do open world properly (like The Witcher 3, where most of the side quests are more interesting than main quests in other games). The Batman Arkham series is the best example of that, Arkham Asylum was so much better than Arkham City because of it, even though Asylum's bosses were mostly boring, City was just so annoying to play with all the "go to point A to the point B of the city" while beating up boring enemies.
I really hope the linear games make a comeback. During the last console generation they were mostly shit because of almost to no content and mostly boring story and characters, but at least you knew what to expect from the get go, they didn't pretend to have a lot of value adding a lot of boring and lazy content like the open world games tend to do.
ii. Grinding and random encounters are other really annoying ways to make your game pretend to have a lot of content, this makes most of the JRPGs shit. Chrono Trigger is one of (if not the) my favorite single player games of all time, but I could never get to like any other JRPG I have tried because of random encounters and grinding, they are just really annoying mechanics that no JRPG developer wants to get away from.
iii. Progression systems have no place in competitive games. If I can't play at the same level with a new account that I play on an old one because I haven't unlocked boosts, abilities or items yet on a competitive game, I don't even start playing the game. This is something that mainly happen in Call of Duties and Battlefields. TF2 is also guilty of that, if I hadn't started playing in 2009, when there were only some few unlockables, I would've probably never kept playing.