The creator of systemd (Lennart Poettering) has recently created a new company dedicated to bringing hardware attestation to open source software.
What might this entail? A previous blog post could provide some clues:
So, let’s see how I would build a desktop OS. The trust chain matters, from the boot loader all the way to the apps. This means all code that is run must be cryptographically validated before it is run. This is in fact where big distributions currently fail pretty badly. This is a fault of current Linux distributions though, not of SecureBoot in general.
If this technology is successful, the end result could be that we would see our Linux laptops one day being as locked down as an Iphone or Android device.
There are lots of others who are equally concerned about this possibility: https://news.ycombinator.com/item?id=46784572
I can’t imagine anyone sane would hold onto the belief that it will remain just “a nice feature to enable” after looking at the historical encroachment of commercial interests in mobile phone boot chain setups. I tell you the truth that after widespread adoption this WILL turn into a “not nice feature that you cannot disable”, and you can forget about enrolling your own keys as well.