Right now, the only way for an Event or Recording to show up in an Area page is if it's linked directly.

Example:
https://musicbrainz.org/area/5245129b-a7ef-4dd0-86f0-e7e466c9419b/recordings

All of those recordings are directly linked with "Recorded in" or "Mixed in" relationships to show up.

These types of relationships are constantly being removed from MusicBrainz when editors see that the Area is already present in the affiliated Place (studio, venue, etc).

Example:
https://musicbrainz.org/recording/fd779ae1-1a8f-41de-a140-a22466acdb0f
https://musicbrainz.org/place/15a0bb96-2787-4747-ab24-2898e6d832d2/performances

The issue that I have is that without directly linking dedicated "Recorded IN" credits, these entries won't show up in the area page. I think we're missing out on a lot of really good cross-linking and database criteria. I'd love to know which bands were recording in the same city at the same time! Or see what was recorded in a specific city over the years period.

I hope I'm making sense.