That lines up with my experience as well. I think though that there is a cutoff where very junior people are almost never going to be highly productive and require fairly constant babysitting.

I think you can mentor/babysit them in a remote environment, but it takes intentional effort.

This is just a symptom of a larger problem though, which is that people try to get useful work out of very junior developers. They should instead treat them as investments that will generate useful work in the future. If you can’t do this, you shouldn’t be hiring juniors.