That is a massive red flag to me too. They are basically saying "you are identical to everyone else, and easily replaced."
It's quite common if you work in a team of engineers, or in a large company with many engineers.
Having consistent machine and OS and app configurations enables better (lower cost, higher reliability) scripting and tooling solutions in things like repos and infrastructure.
Not unlike consistency in language and compiler choices.
Having a consistent setup makes it easier for your organization's IT team to support you, troubleshoot issues, etc. It also makes it easier for you to collaborate with other members of your team, or even other teams. If your coworker Fred comes to you asking for help on how to refactor something, for instance, it will go much more easily if you're running the same IDE with the same refactoring tools.
Organizations establish and enforce standards for a reason.
Or they bust don‘t want to look after a dozen different tools and their security issues.
Wanting to be able to use anybody's machine is very strange, agreed.
From a support/IT perspective though, the closer everybody's machine is, the easier the job is.
The last software shop I worked at, we had a default set of tools and configs. It was a known happy path. You were allowed to adventure off of that path, but you were mostly on your own.