As cool as it would be to see a big shift to Linux, I think you underestimate how deeply entrenched companies are with Microsoft, so unwilling to change, the lack of support for proprietary software, and probably most importantly, the lack of IT support to manage a Linux environment.
I've been full Arch since December in my personal stuff and have been a Sys Admin+ for 9+ years. I would not say I currently have the skills to effectively administer a Linux environment. I could get there, and there is a lot of overlapping knowledge, like the network stack didn't change, but I don't think I'm an outlier.
I recently switched from being the sole IT guy at a small/medium company so a place with about 2k employees. I have maybe met a couple of people within the company IT that I think could make the switch relatively well, and 70% of others that just don't got it.
Long term it would probably be fine, but that's not how companies work in most cases. I just don't think most places are willing to bite the bullet now to benefit later.