These kind of evolutionary theories often make for captivating and plausible stories, they are also pretty much universally false. Similar trains of thought were used in the middle ages for example to rationalize male and female roles in society, all of which have been debunked many times over at this point.

It is unlikely hot springs were omnipresent enough across the environment to have an impact on overall human evolution.

The safety instinct complex likely has components shaped in pre-human and even pre-ape and perhaps even pre-mammal ancestors.

Pressure comes from duration as well as frequency of encounter. A feature encountered infrequently but consistently across many millions of years can exert a pressure equivalent to a feature encountered more consistently for a shorter period.

Also note that the effect size to be explained here is not that large - just a nudge towards relaxation in what seems to be a subpopulation of humans.

What do you think about that?

Sure, but this reasoning you are using could justifying saying just about anything we have encountered in human history, no matter how infrequent or minor, could have influence our evolution. It is incredibly hard to falsify such claims and easy to make them. I don't really know how to respond.

Yeah I personally don’t think such speculation should be treated as “science”, per se.

But, if the science minded shy away from such areas completely, they will be (and are) filled with explanations from people with completely unscientific worldviews and values.

The Dawkinsian selfish gene framing is unfalsifiable. Even Darwin is practically unfasifiable. It kind of comes with the territory.

I think the degree to which such an explanation is a just so story depends on how many aligning aspects we can observe in reality. An example in this case - the more a shower shifts from utilitarian to luxurious, the more it happens to resemble a hot spring. What would be the most luxurious shower? To me, natural stone walls in a natural looking pattern (impractical to clean), no obvious drain, instead the water drains into crevasses in rock (which is mimicked even in run of the mill shower designs), some natural light but not too much, etc.

The problem with the Middle Ages explanations though is that the framework they used to explain things was false.

A false framework producing false explanations does not falsify frameworks in general.

But it is an example where applying a framework doesn't make something more accurate. We can't just rationalize whatever we want because it seems to make sense from an evolutionary standpoint. I also don't know that we should believe that our framework is true. I'm not arguing the truth of evolution, but rather how we apply the fact that it occurred to possibly irrelevant aspects of our life.

> Similar trains of thought were used in the middle ages [...]

The theory of evolution was conceived way after the middle ages, so that seems beside the point.

Similar does not mean the same. A good example is the story of prudism and genitals, where women were expected to be prudent with the rationale that god hid their genitals away.

That's very funny. My first guess would have been the womb. Probably the safest environment most of us have ever been in.