Has it really been that long? Apparently so. Valve originally announced their rebranding of Steam Play with Proton back on August 21st, 2018. Seems like a good time for a quick reflection being halfway to a decade old now with the tech that gave rise to the Steam Deck.
Dang I thought proton was older than that. I remember playing No Man’s Sky on Linux around the time it was released on pc. I don’t remember running a pirated copy of NMS just so I could make it run on wine but maybe I was. (you used to have to do that whether you owned the game or not if you wanted to play on Linux).
Proton is a fork of Wine which is much older than that