The motivation from their side is not wanting to support Linux. There’s a difference between working and supported; support costs them money in terms of every phone call from every person for whom the material doesn’t work correctly, as that means paid trained staff on hand all the time whether you’re having linux issues right now or not. Imagine if one person a year had linux issues, requiring them to hire a full time linux tech with nothing to do but pick up the phone once a year. By putting a roadblock in front that people can get around, it can ‘work’ on that system while they have a leg to stand on to say no to any linux user who wants help they can’t provide.