I've made comments on HN on this point a number of times e.g. https://news.ycombinator.com/item?id=44284083

I had some tedious debate on HN once where I asked if anyone had any pointers to good parallel SMT solvers, only to fall victim to someone dedicated to dying on the hill of "parallelization can never make this kind of search faster" due to (often inapplicable) complexity theory fixation.