Is this a joke? Disabling mitigation to speed up your computer seems like a not good idea..
For example, I found it useful professionally. We're releasing a new hardware model. We're doing some in-depth performance tuning/evaluation. To understand our performance characteristics, I needed us to break down the performance change into improvement due to new hardware and reduction due to new mitigations.
Linking this page in the Jira issue was the fastest way to get the point across what we needed to look into.
It is not, at all, something I would ever recommend to lay people, or use in the actual shipping product.
At home, I don't do threat models or risk assessments. I also don't care that much about 5 to 15% increase in benchmarks, I just hope that the OS vendor makes sensible decisions in regards to safety and performance.
At work, I do care about small increases but I would never just copy some random kernel options found on an otherwise empty web site. Cargo culting useless or harmful options is a very tangible threat.