PKD’s books didn’t generally sell all that well during his life. In those days the sfbc picked up everything. And most of his books were OP when he died. I can remember having to scrounge around for them.
Hmm. In light of that, maybe it would have been more accurate if I said he was famous rather than popular, and for all I know it was only the Science Fiction Book Club that gave him that degree of fame?
His stuff is weird, and therefore a niche/acquired taste.