How long should a game's online functions be supported for?

Wasn't there going to be a PC version?

I don't even know how most games work. Say for a game like Call of Duty, does Activision provide the server's or does Microsoft and Sony? If the former then why do they want a yearly fee to play online? Regardless there should be a minimum if they're selling you a product advertising that feature, but the reason I'm asking is because I don't know and I want to know more about it, gayass.

Devs should just be forced to make dedicated server support in their games. Left4Dead 2 is practically dead and on life support. There's only a few thousand players a day. But all of them are in dedicated servers.
And what is Valve losing from these dedicated servers? Nothing. There is no excuse to not have dedicated server support.

Get them to move onto the next game in the franchise, if there is a sequel, or budget cuts resulting in the servers going offline.

Ideally? Forever.

Realistically? a 5 year plan minimum, ending with the company giving out free tool to allow user-made/maintained servers, that should be available for atleast 2 years after the server closes (by then the software should be available on third party download sites and torrents)

forces them to buy the sequel

It depends, some companies hosted their own servers and some didn't. Microsoft didn't host the "servers" for Halo 2 and Halo 3 as what most people typically think of as a 'server' which was an individual server that pinged a master matchmaking server that pinged a console to tell it to connect to an IP hosting the server, being on whoever was picked to be "host".
The case being though, when a company is hosting both, the master matchmaking server AND the game servers, when the servers are discontinued the games are basically dead when they pull the plug and take both the matchmaking and server hosting software with them. Since in those cases the host software is not bundled with the client software.

This.

If you put a component in your game it should last as long as every other part of your game.

Yes, it'll be F2P from what I know.

Yep. But for some fucking reason there's still North American release date, it's only out in Japan and Russia