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.
Not that I disagree, but they get the exact amount of credit their licenses require.... a small-text listing on a "credits" page buried deep in the system settings.