It's much more than that. It also allows one thread to make progress while the other is waiting for memory loads, or filling in instruction slots while the other thread is recovering from a branch mispredict.
Compilers tend to do a lot of pointer chasing and branching, so it's expected that they would benefit decently from hyperthreading.
Compilers tend to do a lot of pointer chasing and branching, so it's expected that they would benefit decently from hyperthreading.