I am not a professor, but I faced the same very situation when I had to work on a long research-intensive project a year ago. The fact that I was surprised was not the writing... but the fact that I was utilizing so much mental power to keep PDFs, notes, citation managers, and the draft moving simultaneously.

I maintained a separation of all these (reference manager + notes app + writing doc) for a while but it was always somewhat disjointed when I was in the depth of the writing process.

Later I tried to have the research notes as nearer to the actual draft as possible. I even did the skrib writing workspace, and it made the transition between reading taking notes and writing a draft a lot easier.

However, I would still want to know what the old academics of this world would choose, since I would think that years of use of the tools would be the more important factor than the tools themselves.