Unable to spawn on vehicles, squad mates, or beacons if on a captured objective

Still having this problem myself. Only partial fix I've found is that when I want to spawn on a squadmate, I can click their name in the corner of the spawn screen instead of clicking on their character icon as it moves around the map. But that only works when I have squadmates that actually ptfo and not hide in spawn, and only when they can get out of combat long enough for me to spawn on them.

Since it might be relevant, playing keyboard and mouse on PC, and can confirm it's also an issue in Breakthrough game mode.