@saxnot any website can post your resume its true, but linkedin does admittedly have an advantage in that regard a random website doesnt... that is, since people are centralized there is some reliability in the recommendations you get being legitimate, and more useful when it comes to an employer trying to evaluate your abilities.

To have that from a non-centralized server there would have to be a framework in place (like GPG signing) for people to verify their identities and associate that verification with their recomendations. In turn that means the mechanism for signing, like GPG needs somehow verify someones identity in a useful way (something like keybase.io).

So doable, but not often used sadly