I should clarify I'm not claiming that an SRE is more valuable than a Developer outright. I'm saying that most highly qualified SREs are also Developers, while highly qualified Developers are not also SREs, so the amount of skill/knowledge required to attain the salary is more burdensome for an SRE vs a Developer. If anything, my statements should be construed as a realization that its a better career progression (at least when focusing on salary) to become a Developer than it is to go into Ops because for whatever reasons society values Developers more than Ops.
If 10 guys all showed up on your door with a magic box that would give your business $100k in added shareholder value, you'd be rational to pay somewhere between 0 and $100k for it. The top end is determined by how much new value is added, but what you end up paying would have to do with how each person priced it -- if there were more of them, the thing would probably cost less unless the providers of it colluded.
Just keep in mind there's a push and a pull and, even if a factor adds a lot of value, it can be cheaper than a less-value-added one, because factor prices are set by supply and demand, not their relative value-added output (which can also depend on how well they're used, which is why some companies can pay so much better for exactly the same work as others)
(Which is really a broader recipe for success in business generally: figure out how to employ factors of production -- people, capital, etc -- more profitably than they cost to purchase in the relevant markets, and BAM, you've got a profitable company)
[1] https://en.wikipedia.org/wiki/Best_alternative_to_a_negotiat...
Companies are complex systems with many moving parts and team dynamics. If a new feature gets released, do you attribute incremental revenue to the dev who coded it, the product manager who specified it, the sales team who sold it, the marketers who described it, the executives who hired the people who did any of the things above, etc?
Bottom line: "value creation" is a totally sociological construct having more to do with the organization's culture (who's most highly valued) than any objective metric of "value add". You need to be in a place where the people empowered to make decisions about pay perceive that the work you're doing is valuable. No more, no less.
Hiring is supply and demand. There are more competent accountants vying for the same jobs than there are developers. More developers than there are SRE's.
The rarer the skill set, the more expensive it is to hire.
I could argue against you too, for example, you say "competent developer in numerous languages and environments", that's really just a small fraction of what computer science is really about.