Doublechecked it, and it's 4% based on steamdb for 2023, and 5% for 2024 That's of course counting only these three.

Steam released 14500 games in 2023 (all engines).

Unreal on steam was 2400

Unity was 7400

Godot 400

Before the Unity suicide, I doubt it had 10% either. And you know, making games takes time, so in terms of released games, we might still not see an uptick.

But I do think newly developed, particularly indie titles will go beyond those 10%, and maybe even quite easily so.
There's not many statistics out there, so here's some horribly biased ones: https://gamefromscratch.com/godot-popularity-at-gmtk-jam-2024-explodes/

This is from a gamejam held by a particular YouTube channel. That YouTube channel has an ongoing series about making a Unity game, nothing about Godot yet.
But it is a gamejam, where people sit down for just a weekend to make a game, so people will be much more willing to try a new engine out. Although they'll typically have some prior experience, since you don't want to spend the whole gamejam learning an engine.

But yeah, those caveats notwithstanding, that still is a significant growth for Godot.