Because I work in a highly regulated industry. We have to qualify/verify/validate everything that we use, and we all have to be standardized on the same thing. I'm currently struggling to get unit tests working smoothly -- we have to validate the "plugin" that we use to execute the unit tests (MSTest... part of Visual Studio), which means that we need to write requirements and then test those requirements. We're writing requirements for MSTest.... I'm pushing to get a CI pipeline set up so that our unit tests can be run automatically with every check-in, but we'll have to write-up requirements for whatever CI tool, validate that it works with our existing source control, validate that the unit tests execute properly, document it all, review it all, sign off on it all within our document control system. etc... Switching to an entirely new IDE I think would make people's heads explode. Personally I think that we make things excessively hard on ourselves -- I'm endeavoring to reduce some of that pain.