Fair, and still not something most companies can pull off. Again, without risking running into anti-trust laws like MS did.

Do you seriously think that you can go to all your vendors (if you were a business owner) and tell them, "You can't use Atlassian when working on anything you sell us." How will your business actually compel all those vendors to drop their use of Atlassian for that work? How will you verify compliance and why should any of them sign a contract with you with these restriction? And if they do, how will you avoid anti-trust violations because almost certainly the only way you could talk them into signing such a contract would be to be a massive company throwing your weight around (like MS did with hardware OEMs back in the 90s, among other things).