I no longer use whiteboards if I can help it; while I trained back my fine motor control after my stroke sufficiently well to perform most other related activities, writing legibly on a vertical surface in front of me is not something I specifically trained back and doesn't seem to have "come for free" with other trained skills.

When I used them, I mostly used them for collaborative thinking about (a) to-do lists and (b) system engineering (e.g., what nodes in the system perform/receive what actions; how do those actions combine to form end-to-end flows).

I far prefer other tools, including pencil and paper, for non-collaborative tasks along those lines. And these days I mostly work on geographically distributed teams, so even collaborative work generally requires other tools anyway.