In addition to what others have said, liability is also a factor. If you don't work out, it's because you somehow lied about being able to do the job and not that their training was inadequate or that they failed to prepare/equip you. Additionally, less training is required theoretically, which means less cost on the investment of a new employee. Less risk overall for presumably better results.
Lack of experience also means they have deniability not to hire someone. I've had interviews go south immediately when the interviewer realized I was LGBTQ+ (stealth fail), but their stated reason was that I didn't have enough experience with MacOS. I've done volunteer work in my field for the UN using MacOS, but alas, I was "too inexperienced". The higher the requirements, the safer those sorts of dismissals are for them to make.