bxl-forever
This is in fact a problem with the StreetComplete mobile app.

In this area we have an extensive decription of all footways and sidewalks, and they connect at places where people would naturally cross the street.

The point is properly tagged in OSM as being an "unmarked" crossing.
https://www.openstreetmap.org/node/7924103745

The problem is that StreetComplete seems to ignore the difference between marked and unmarked crossings and bugs users to fill information even when there is nothing visible on the ground.

I recommend you just ignore those quests in SC.  I’ll try to report this problem to the SC developers and ask for a fix.

Closing this note, as this is not a data problem in OpenStreetMap.