I completely support an option to add game keys for Steam or non-steam Windows to FF14 accounts.

I know others have had issues with it, but I've had zero issues with the Steam client or overlay in regards to playing FF14 and have been happily using the Steam version of the launcher to log into my FF14 windows account since I bought an additional steam version of the game in 2015. I've used the steam version of the game for over 3000 hours in that time and losing the ability to play the Steam version specifically, thus being denied the steam account integration and community features that Steam provides to users is a real kick in the pants when the change was in no way communicated that users in my specific situation would be impacted at all.

If the option were available, I would instantly add the steam key to my mogstation FF14 account if I could then successfully log into the game using the Steam FF14 Launcher.