Yeah, the earliest attempts weren't good, but I haven't heard of any HT problems post Pentium 4 (apart from Spectre-like vulnerabilities).
I assume OSes have since then developed proper support for scheduling and pre-empting hyperthreading. Also the gap between RAM and CPU speed only got worse, and CPUs have grown more various internal compute units, so there's even more idle hardware to throw HT threads at.
The end result was that doing WebSphere development actually got slower, because of their virtual nature and everything else on the CPU being shared.
So I ended up disabling it again to get the original performance back.