Amen! But I know what my company would say. "Training devs and SRE on a new language is too expensive. And there are too few Rust devs in the job market, and the ones there are are too expensive to hire."
On the other hand, I have experienced a situation where a fairly young group experienced tech burnout from having to learn too much at once. It's a really tricky balance. I was definitely on the side of "We're programmers! Learning programming languages is like drinking water for us" originally, but now I step back a bit every time we think of introducing new tech. Still, spiking a solution in a couple of different languages seems awesome and I can think of a few projects I've worked on that would definitely have benefited from that.
Cloudflare still seems to operate pretty similar to a startup despite now being huge. These days, it seems like a lot more companies that begin as startups are preserving more of that experimental, innovative culture to their later stages. Y Combinator, and others, definitely deserve credit for positively influencing the industry.
1. Cloudflare has an unusual structure in that we have a three engineering groups: the core engineering group that builds things that the product management team specify, a totally separate disruption group that works on riskier bets, and a crypto research group.
2. I strongly believe that letting people work in languages they love has a huge advantage. Engineers want to learn new skills (and those that don't we don't want to hire) and so letting them do that means they are happier and do better work.
3. Small teams do more than large ones. The teams that work on Cloudflare products are very small and agile.