Well the fact of the matter is he didn’t say “All Evangelicals..etc” so I don’t know how you can say what he said is “a lie”.
He was an Evangelical, so he knows from personal experience and as you point out, he is an historian so surely he knows what *some* Evangelicals believe and practice.
As an alleged expert,he is making a general statement about evangelical beliefs, i.e. if you are an evangelical you will believe believe thus and so. The general statement is a lie. As an academic, he should know to be precise in his language. If he wanted to carve out a place for evangelicals that are not covered under his statement, he would have cited the statement to be his opinion.
NOW the facts are coming out; after I apparently wasted my time replying to a 'factiod'!