Its isn't a solid fact I will admit, however even if there is only one isp (like around here) they have different plans you can buy. More money = faster internet. And yes I will agree that other things like having to share your internet with family will slow it down, and yeah youtube for sure because it works like a torrent program and attempts to give you the highest quality video your internet can handle unless you tell it not to. But no matter how many odd flaws you find in my statement, in a world ruled by money and the bottom line (like earth) large game makers devote their resources to the things they feel will appeal most to the people who pay for the game.
Its a sad but true reality, but I think as long as these technical and economic barriers exist, there will always be room for playing solo (Bioshock Infinite) or online (Battlefield 3 and 4).
Still, AI bots would be very cool to have in our multiplayer games.