Plus, as ME Andromeda has shown, having all single player content and care stopped while they continue to push the Co-op/Multiplayer full of micro-transactions is a wee bit annoying.
Sure, the multiplayer aspect is "optional" , but people don't pick up a ME game (or similar) to play multiplayer. For me it's all about having an interesting (or silly) story to enjoy and have fun with, and poke at what consequences might spiral out from my actions as I play through. So while on a certain level, I can't rant against optional multiplayer, it does seem silly to strip away resources that could go towards improving the main focus of the game.
Most of my gamer friends are in different countries and on wildly different time zones to me, so it's not as if I'd ever really get into regular co-op play with them, and having to deal with random strangers who get introduced to you for half an hour, who might or might not speak the same language, does tend to suck any thought of actual strategy away turning it into a general crapshoot.