This may not be a discussion for this Forum, but the idea that she brought "conservative" protestant revivalism to mainstream culture, can be questioned. Pentecostalism was considered out of the mainstream of evangelicalism...even heretical. The idea of a WOMAN preaching, much less running a church/denomination, was considered very unbiblical/liberal for the norm.
While she believed in NOT boring her audience, her presentations and promotions, were regarded as an affront to the dignity of the Church/Gospel.
Her not scapecoating those of other religions, and not making those of different races feel unwelcome to her services, was out of step for many fundamentalists/evangelicals of that time, who considered her too liberal/apostate in those matters.
Anthony Quinn, wrote glowingly of the many who were fed/helped by her church, and said she was more fascinating than Garbo or Hepburn.
Looking at the companion book, it is as if the author has "discovered" a religous movement, already over a century old, with 10s of millions of adherents, and lacks that perspective.