Resident Evil 5 is not for everyone and might be disappointing to series veterans but there are elements of the game that make it genuinely enjoyable and fun if you're willing to look past it's flaws and play with a friend.
As the most action heavy game in the series there is definitely something to find enjoyable about playing a Resident Evil game that leans in to almost being a power fantasy and it has to be said that it's not all that different mechanically from 4. It seems that in order to give it a new gimmick, so as to differentiate it from the last entry, they tacked on a co-op element to the game. This co-op experience is actually an incredibly fun time to go through with a buddy but, as a result of designing the game to be this way, it is a pretty abysmal single player experience.
The game also falls into some of the worst gameplay tropes of it's era with an abundance of tedium such as turret sections and having to rely on your partner to proceed through to the next section of the mission, presumably to build a sense of teamwork or something. The series has always been linear but this title probably instills the sense of being the most truly on rails with boss fights that give zero lee-way to how they can be approached (that final fight in particular being one of the most frustrating bosses I've ever encountered).
So far everything I've said comes across like the game is terrible but I'd be lying if I said that I didn't have an absolute blast with it despite it's flaws. The pace of the game is set to blistering the whole way through, the action combat is very tightly polished and playing through such an unashamedly self serious game had me grinning throughout a large chunk of the game. Mercenaries mode is also a really exhilarating experience that capitalizes on the great gameplay elements and is worth picking up the game on it's own if it's on sale. Also the DLC with Jill and Chris investigating the mansion from Resi 1 had some fun puzzle sections and was a very classy bit of fanservice for those that enjoyed the first game.
Overall a deeply flawed campy mess that's extremely fun to co-op despite and appeals to those who enjoy the more action-focused side of the series.

Behind the occasional poor performance is one of the more in depth farming sims out there with a new crafting system to make every resource feel valuable. Some of the minigames feel a bit pointless and distract from the addictive routine you find yourself in. The characters aren't as endearing as some of the previous SoS/Harvest Moon games and the lack of acknowledgement of your relationship by the characters you romance leaves you feeling like the relationship is only actually happening in cutscenes.
Outside of some of the gripes though the moment to moment routine of the game is very in depth and addicting and probably the most refined version of the farming sim formula.