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.
Valve’s contributions to Wine can be used without using Steam’s DRM-based client such as in applications like Bottles and Lutris. However, we should call on Valve to release the steam client API to the public and to only distribute DRM free games (like GOG).