Their plan did get off to a rough start, initially they wanted game devs to provide native Linux builds despite there being near-zero upside to doing so at the time, which unsurprisingly went nowhere and led to the first generation Steam Machines dying on the vine. Thankfully they realized their mistake and shifted focus to Windows binary compatibility, which has been far more successful. It took a long time and the success of the first-party Steam Deck to convince third-party manufacturers to give Valve another shot after their early SteamOS partners got burned though.