[joshuamorton]

THere's at least one big issue here, which is that you're pretending that a website is like a building or a dam. If that were the case, a company like Google would have a (relatively) small team of SWEs who "built" things, and a much larger team of SREs who maintained them over their operational lifecycle once the SWEs were done building the thing. But that isn't the case.

Software systems (at least in competitive consumer markets) are constantly changing and evolving. To use the dam analogy, there's constantly a team of people making the dam taller or wider or deeper, even while the dam is running and producing power.

All the SRE teams I've worked with have done a bunch of things that go beyond "operations". They are usually consulted at the design stage, to make sure that the thing is going to be built reliably. They're also responsible for ensuring ongoing reliability as all new features are added. That means that the features themselves don't impact reliability, and that the process of adding new features doesn't impact reliability. None of this work has a reasonable analogue in your dam analogy, except perhaps as some combination of consultant and regulatory body.