Yes, the fee applies to eligible games currently in market that continue to distribute the runtime. We look at a game’s lifetime installs to determine eligibility for the runtime fee. Then we bill the runtime fee based on all new installs that occur after January 1, 2024.
This is still up on their FAQ:
I love that their “proprietary” method of determining installs is to just look at the # of installs reported publicly by Google and Apple app stores.