Can Opensource OS be censored by removing all boot firmware?

So it dawned on me that if manufactures wanted to remove the option to install another OS on the system, they could. However, The manufacture would probably go bankrupt. The reason for this is because that sooner or later you will always have to upgrade with windows, but that is not the case with linux. Of course, they would try to stop installation of linux in the first place, so that is not really relevant. But not only would linux users not buy from them, but server hosting companies wouldn’t since there are specific OS systems to host servers (and of course LINUX). There is also no buy in from government pc’s around the world, since the usability would be 0. In essence, anyone who would try this would bankrupt themselves. Then let’s just assume for a moment that this did happen. Ok so, like it will ever work. With the hacking and modding community out there, this will never fly. They can just open the system and install their own chips, just as they did with consoles. And that is if they are even stupid enough to buy from the supposed manufacture of the locked OS pcs. So yeah, it will never happen. Even if there was a massive push for this, we could all just make our own pcs, which would then put other companies out of business. Not only would that hurt one manufacture, but the entire economy. So no, the idea is gone and settled. Computers with linux and other OS systems are here to stay.