(Just wanted to clarify that I personally don't have any game projects like this yet. This is a suggestion in general for the future, as I know how much time it takes to implement any ideas).
I agree that a filter on AArch64 is not quite what is needed. A filter by tag does pick the right list of games. 🙌
For such devices, the "portmaster" tag (https://itch.io/games/tag-portmaster) is the right one at the moment. Thanks for pointing me in the right direction!