Unlike in the sciences, historians publish their best and most popular work in books. Not reading books is therefore antipathetic to being a historian. Also, they were a she.

Anecdote: When I was in a history graduate program, part of our training was a "written exam" based on a list of 200+ required books (and several hundred more recommended ones). There literally was not time to read every book, so we all got a crash course in how academics read -- get the author's argument from the intro/conclusion, then get the structure/evidence/case studies by skimming the chapter list. By the end, I was able to "read" a book in about 30 minutes, but there was no way I could actually _read_ the book. The goal was to spend as much time as possible reading primary sources, not books, because that was the "value-add" for an academic historian.

Yes, I got into the habit of using books in this kind of instrumental way during my PhD, of just taking what you need and nothing more. It can't be avoided, but in the long-term it's healthy to select some choice books to read in their entirety, if only because otherwise you'll learn nothing new. There should be some balance between focusing on what's immediately valuable to you, and exploring new ideas. Books are also usually written as wholes, and are for that reason are often best understood when read from start-to-finish.

"Popular" among public is not the same thing academic seeks. Afaik, there are not that many historical books in small sub-specializations historians typically work coming out all the time.

Historians publish their history in books, even the history targeted at other historians.

I mean 'popular' for an academic book, i.e., widely read by other academics.

I can assure you that historians prioritise monographs over journal articles in the UK and US, and it's there that you'll generally find their best work.