Isn't it mostly due to habits?
As for lock-in -- maybe wrong phrasing but tools being available only on one platform and taking advantage it's the most popular platform is not the best thing. IE in the past being available only the Windows. MS doing lot's of exclusive deals with public entities (municipalities, government agencies, schools) with combined deals on Windows and office forcing everyone to use `.doc` format (and thus having to use office, and thus having to use windows) or basically nourishing the notion of "windows is the PC" right from the school age thus anything different being "pain to use"?
All big companies do it, Google being poster boy of it nowadays
Even Valve with SD isn't doing it out of pure intentions - just a way to counter MS efforts with Xbox/Windows store
This reply is being typed on MBP with macOS, I manage a bunch of home family PCs with Windows, I do have Linux on SD and servers. I wasn't aware that WC only allows all-hail-praise of MS and Windows