Microsoft cannot quite market the limitations of UEFI, notably restricted boot. Truth be told, boot-time malware is not the real threat but mostly a conceptual one (with proofs of concept put out there by security researchers), and moreover UEFI is easy for malicious entities to bypass [1, 2], as proven before (Torvalds, clearly not a fan of all this, saw it coming). Just like DRM, it hurts legitimate users and developers the most. No wonder there is an antitrust complaint over it,
"Truth be told, boot-time malware is not the real threat but mostly a conceptual one...""A critical vulnerability in Internet Explorer 8 is being exploited in the wild and full information about how to make use of the vulnerability is now in widespread circulation. The recent attack on a sub-site of the US Department of Labor has revealed the attackers were in fact using a new exploit for a 0-day vulnerability which only affects Internet Explorer 8," says this report. So why does Microsoft obsess over boot-time?
UEFI addresses an issue which hardly exists, it is a solution in search of a problem. A highly-anticipated Debian version was released the other day and it is not compatible with Microsoft's latest hardware restrictions, says Sam Varghese. To quote:
The Debian GNU/Linux project released version 7.0 of its well-known Linux distribution on May 4, two years and three months after the last version came out.