Import POI

  1. Import POI (documentation) can be done via GPX (waypoint) files, if import them as temporary routing overlays to help on route planning.
    Import them as bookmarks is a more serious case, as bookmarks remain permanent on app exit, unless user explicitly clears them.

In any case obviously it’s not recommended to import large files with hundreds / thousands POI, because that will hurt app performance, also depending on device specs.
First should filter externally the poi files, so can import only the needed data.

No.

Only when show map layers with large number of poi from small zoom levels (we avoid it).

That topic has specific purpose and we should keep its discussion focused.
It’s about show more POI into offline maps (some may exist in map files).