[sir-alien]

You might be right in "most" cases but looking at the benchmarks, there is quite a few cases which are used a lot in everday computing where performance literally hits rock bottom. Video rendering went from 600 frames per second down to 200 frames per second. That is a 60% or more performance loss.

[GrayShade]

Look at the default mitigation; the full one disables HT. Unless you're a cloud provider, the default is probably enough.