I mean, maybe temporarily done so that you can patch up some higher priority (more broken?) stuff, but DONE? Pushing the envelope is how you progress, and in this case also how you can learn.
Even assuming unlimited developer resources, will you really notice a 0.5% difference in production, especially when taking things like network latency into account?
My point is that hyping over raw performance is misleading at best. If performance is the only thing that matters then we wouldn't have operating systems with abstractions - everybody would program against the bare metal in assembly. One should weight the pros and cons carefully and reach a balanced trade-off.
It's about progression over time. If someone didn't do it, we'd be leaving significant performance gains behind. That means more servers, more electricity and more money for everyone.
I'm not going to do that for my app but it's nice that there are people making these improvements for the benefit of everyone that uses their server.
When you take into account many small improvements, across all deployments, over time, they can and do add up to significant improvements.
There's a extremely well known saying that speaks to this issue, goes something like "Preoptimiztion is root of all evil."