The ability to conceptually understand what they're doing is exactly what I'm testing for when interviewing. Writing a full program on a whiteboard is definitely not required for that. I can get that from asking them question, observing how they approach the problem, what kind of questions they ask me etc.

I definitely don't want them to do just the bare minimum to survive or to need to ask me for advice at every step (had people who ended up taking more of my time than it would've taken me to do their job myself).

I've never needed to write more than a short snippet of code at a time on a whiteboard, slack channel, code review, etc. in my almost 20 years in the industry. Definitely not to solve a whole problem blindly. In fact I definitely see it as a red flag when a candidate writes a lot of code without ever stopping to execute and test each piece individually. It simply becomes progressively more difficult to debug the more you add to it, that's common sense.