That’s not that long in the grand scheme of things. It’s been almost 20 years now since Steam was opened to third parties. Valve stopped most of the game development once Steam got into dominant position.
Valve never stopped game development. They just haven’t released any new games in a long time unless you counter Counter-Strike 2 as a “new” game or don’t consider any maintenance, changes, additions, or other continued support as part of development.
They have been operating that way before they even made Steam.
That’s not that long in the grand scheme of things. It’s been almost 20 years now since Steam was opened to third parties. Valve stopped most of the game development once Steam got into dominant position.
Half-Life Alyx was fairly recent