Do you really want a dev environment where there is only one way of doing things?
Even if it's not the best way. If it's for more than one person, for the sake of sanity, pick a single way to do normal tasks. It doesn't have to be static (changes to the process/tooling can be trialed and applied), but it should be single.
I've built developer tools for big teams that improved productivity and increased my and others' happiness for a living. And I'd shred every single commit to those tools in a heartbeat in exchange for an environment where you don't have to head-scratch about what process and tools other people were using to make changes to the same code.
I hesitate to criticise it, but I don't think such an environment would be polished. A frozen environment is one which can't be improved, so will naturally stagnate. You couldn't achieve a state of being "extremely polished" because those who cared to do the polishing would be denied the ability to do so because it requires change in order to do so.
The obvious counterpoint to your statement is that if your mentality held sway, we would never have had Git and would still be on SVN.
To put another way; I HATE git, I LOVE Mercurial, but Git won, it's ubiquitous and Mercurial is not that much better.
Having one thing doesn't ensure at all that it will be polished. In fact, it's more likely that it will stagnate.
Hg and Git are both GPLv2.
* Huge monorepos and thousands of developers
* Repos with huge binary files
* Repos with few developers
* Personal repos.
* CD repos
* Interconnected repos