I don't see why this is an issue. The affiliate relationship is disclosed in the footer, the recommendations are coming from a legitimate historian (Andrew Robe

I don't see why this is an issue. The affiliate relationship is disclosed in the footer, the recommendations are coming from a legitimate historian (Andrew Roberts) instead of from the site itself, and the site is adding value both by reaching out to Roberts to get his recommendations and by interviewing him to get context on why he recommends them. It's definitely not one of those "we searched for this word on Amazon and here are the first five books that came back" blogspam pages.