If Rust was really that superior, would companies using it not have a competitive advantage in the market?
In theory, yes, but there are two problems:
(1) You need to either hire or train someone to write in Rust, and neither is trivial amount of effort. And at the end of the day, you need to push features out. Let's be real: you can find someone to write JavaScript to do full stack development, anywhere in the world, for a cheap price. Rust? The code may be more robust and easier to maintain in the long run, but it's hard to do that unless you already set up a team for that.
(2) Most software companies don't actually care that much about the language they use, the tech stack, or their infrastructure in general. Remember there are lots and lots of software companies that are not Google/Meta etc, and they are not at the bleeding edge of have state-of-the-art infrastructure. Saying that as someone working at a company with thousands of developers, and there are millions of old, ugly, almost unmaintainable Perl code in our core infrastructure running right now. From outside, it all looks fine.
People are happy in Ivory towers, and often ignore better high-level llvm compiler options. =3
People love to downplay long startup times or longer runtimes ("Who cares if it takes 1s to start?" and "It takes 17s vs. 1s, big deal, you are overreacting!") but it does add up with time and makes people dissociate and stop caring. I've seen it (and it happened to me as well).
But many companies are definitely writing new projects in rust rather than C++, including Big Tech.
It would also have no other ecosystem. No books. No tutorials. No mentors. No libraries. No frameworks.
And even as it got those things, they would remain immature and incomplete for a long time when compared to the ecosystem around languages that are decades old.
I could also make an operating system that was superior in every way and it would fail because there would be no apps for it.
For me it'd have to interact seamlessly with other languages and enable incremental adoption, otherwise you can't swap one with another.
But you can swap a floppy disk with USB flash drive if the PC has an USB port, so that's what I mean by superior..
A language that allows incremental adoption will necessarily be limited by that necessity -- another trade off.
When USB was new very few computers had USB ports but nearly all computers had floppy drives. Floppy disks were cheap and flash drives were expensive. If your purpose was to share data then using a USB Flash drive at that time was an inferior experience. If you had a lot of data, a writable CD was a much better choice. If there was ever a period that USB drives were supreme for that task, it was brief. With higher speeds and greater adoption, it quickly became much better to use the Internet to exchange data.
Money is the biggest parameter, and it would not make number go up in the short term. Tech stacks are in inherently a long term investment and companies are conservative to do big reworks like that.
So companies with lots of earning potential in greenfield projects might indeed have a competitive advantage, while it's more difficult for those with products that have a large existing C++ codebase.
> But Rust is better in the same way that Betamax was better than VHS, Mastodon is better than Twitter, Dvorak keyboards are better than QWERTY, Esperanto is better than English and Lua is better than Javascript