Yet GPUs which take HT to the next level by having thousands of "hyper-threads" work very well for scientific computing.
Just like HT.
CPUs target low latency (they switch often). GPUs target high troughput (they switch rarely, only when needed).
High troughput algorithms dont have problem with a lot of threads. Low latency algorithms have problem with a lot of threads (they need lot of cache memory because of constant switching).