True - but as the other HN thread (that I can't seem to find anymore ><) pointed out, if Microsoft's requirements were planned as an attack against free software, it would be an unnecessarily complicated and ineffective one: There is nothing stopping anyone from writing Linux drivers for the new RAID mode - and I guess if more models with this setup show up, eventually someone will write one.

On the other hand, Microsoft could have easily gotten a much more "robust" lockdown - by simply demanding mandatory, unchangeable Secure Boot like on the ARM tablets. But they didn't do that.