I don't see how. Working as intended would be "And then the gamedev landscape is dominated by open-source tools because you can't make closed-source tools in-house without giving up on the ecosystem." This is very much not the case today, the market is dominated by closed-source engines (sorry Godot).

Seeing as that scenario didn't come to pass, the only result is a net loss of games that could have been made (or made cheaper) by reusing Carmack's code and instead weren't. Maybe some of these games would have been proprietary, but it's still a net loss that they weren't made at all.