I usually only do multiplayer with friends so single player for the most part for me, the games I do multi in I also tend to really enjoy more because they're with friends.
Multiplayer all day. Also, wow, all these emojis randomly appeared below when I started typing. New update? Cool.ceptile:
In this day and age I'd say the more apt question would be to ask single player, COOP, or multiplayer. Multiplayer does encompass coop true, but generally they're listed separate on the box for a reason since multiplayer can be either cooperative or competitive play with others separating leaves multiplayer to incorporate the competitive aspects while coop is clearly cooperative play. To answer the question it depends on the game, Im not particularly a fan of most pvp aspects in games as dealing with people is almost always a bother especially if you go to actual physical tournaments as I used to for SSBM and any game with forced coop or scaling based on a full party rather than the party you bring isn't usually high on my list either. I have a usual gaming partner and quite frankly he's a bit sub-par so if a game is scaled to 4 people for example the vast majority of the burden falls on myself and that can be drag depending on what needs to be done. We've been playing Metal Gear Survive lately and mostly using in-game resources to play so far rather than bring resources from single player to railroad the game since it's in a precarious position of either being incredibly easy or too hard for two people. Bring in weapons that are more apt for our level and the game becomes boring trying to scavenge with non-optimal weapons on the other-hand has been a bit of a chore. If I don't build defenses we don't have defenses placed, if I don't get materials then we quickly run out after token defenses, if I don't watch the map constantly wanderers get through so in a game like that having to do everything to ensure it gets done gets a little tiresome, but it's worse IMO if you simply railroad the game with over-powered items. Meanwhile something like Far Cry 5 the coop doesn't really matter as the coop player is essentially just replacing one of your AI teammates (if you're at the point where you can have 2) and is more or less there. Being a human your coop partner can get detected more easily and cause a few problems, but those problems don't have a large impact either so it's nice to have somebody else around on occasion otherwise you could just go play Skyrim or something by your lonesome.
The most fun I ever had playing co-op was Tales of the Abyss. The fights get super-chaotic with trying to get everyone in position to use the element-fields (the game calls them "Fields of Fonons") to trigger stronger artes, while staying away from the enemy units (especially on Mania mode, where everything kills you in one-two hits. Typically, though, I prefer single-player games.
Some story-centered single player games (Like Portal, Pokémon, Metroid, etc.) are super fun to play just by yourself, because they really immerse you into the universe and make it a fun experience. Most of the time though I prefer multiplayer, cuz playing with friends/other people is always more fun. Smash Bros, Halo, and various party games like Rock Band/Let's Dance (Yes, it's stupid but fun) come to mind!