Depends on how you count it. Asimov and Wells were much better authors and had a vastly greater effect on science and popular culture. They also managed to get out of the science fiction literary ghetto and be read by the public at large. They’re considered authors who wrote science fiction, not science fiction authors.
Hubbard and Rand however sold and still sell tremendously large quantities of books. Way out of proportion to their status as authors. Hubbard in particular sat at #1 in sales for a long long time. It was done by his followers buying the books at retail then returning them to be sold again to distributors. Rand was eventually eclipsed by Heinlein sales wise. Both were self described radical libertarians, but Heinlein could actually write. His stuff is objectively readable. At least the pre-heart attack stuff. “Friday” and “number of the beast” are both fairly awful. “Stranger in a Strange Land” was written in his prime though. It’s kind of dated now of course. As an actual decent writer several of his books were made into films. You’ll never see that with Anne Rand. Her stuff just sucks too hard. Hubbard managed to do it of course, but only by dint of his church. He was also a better author than Rand. Not great, but at least more journeyman level.
