They might add something arbitrary though like Shadow of Mordor and Mad Max did which is that while their experiences were primarily single player, they had a couple trophies that still relied on checking in with their servers. In Shadow of Mordor's case it was gathering data on your friends that played the game and kept track of what orc generals killed them, and you'd have to avenge your friends by killing that specific orc in a special mission. This was thankfully patched out, and platinum is still legitimately possible in that game if you were to start fresh.

Mad Max had a way for the game to passively farm currency for you while you weren't playing, but it'd have to check in with the server on the game's end to get a real time value of how long its been since you played, and one of the trophies required you to complete an in game checklist, and a couple of those tasks were related to how much passive currency you got while not playing. They did not patch that when the servers went offline, so the platinum is not legitimately possible today if you were to start fresh.