Google has used debian as their base. Netflix uses a BSD flavor (I forget which) as their CDN cache. FB used CentOS, not sure what they use today since CentOS is EOL'd.
Debian (and, formerly, CentOS) is a good standard: it occupies a sweet spot between ubuntu server and alpine, in the sense that it's batteries-included and very well-supported (apt/yum), but not particularly bloated.
For other distros, if you're working on non-x86, or have uncommon dependencies, you should be prepared to pull in and build your dependencies from scratch, which is not much fun to maintain.
No problem! If you search around for "Debian vs BSD", you'll find more exhaustive explanations [1], but it mostly reduces to the fact that BSD is more coherent & organized than GNU/Linux; it's more feature-rich in the domains that sysadmins and hackers appreciate, but feature-sparse in the domains "normal users" appreciate. Depending on your needs these facts can be advantages or disadvantages.
I tend to gravitate towards projects like BSD, since they align with my principles, but you do pay a cost in terms of compatibility with common software.
For example, Firefox does not treat BSD as a first class build target, so it's up to community members to build and deploy Firefox binaries, and report feedback on bugs that break BSD installations.
If access to the most up-to-date compiled versions of popular software packages is a big sticking point, BSD-land may not be the right choice. But if you're living mostly in `vim`, `bash` and `man`, and are willing to roll up the sleeves, BSD feels cozy.
It's maybe a 20% correct analogy (don't read too deeply into it, or you'll draw incorrect conclusions), but C++ is to GNU/Linux, as D/Rust/Zig is to BSD.
Having an operating system where the kernel and core userland are developed together is a qualitatively different experience to one that's been stitched together from external projects. I'm not really sure how to describe the difference in experience but the "this is an integrated whole" feel is really quite pleasant as a sysadmin and as a user.
Note that my personal infrastructure is a mixture of Debian and FreeBSD and I dearly love both - if you forced me to pick one of the two to keep I'd be horribly torn.
Debian (and, formerly, CentOS) is a good standard: it occupies a sweet spot between ubuntu server and alpine, in the sense that it's batteries-included and very well-supported (apt/yum), but not particularly bloated.
I use debian for all my personal stuff. The BSD flavors (https://en.wikipedia.org/wiki/Comparison_of_BSD_operating_sy...) are tempting, though. Perhaps one weekend!
For other distros, if you're working on non-x86, or have uncommon dependencies, you should be prepared to pull in and build your dependencies from scratch, which is not much fun to maintain.