I think the rise of the self-contractor market is the fuel. I'd be the first to recognise that some self-contactors (or in today's IR35 vernacular, "managed services") have the experience and skills that you'd never attract on a permanent salary but, in the case of some, the guff on their Linkedin profiles is unrecognizsble from what you see before you.
It's also interesting to see how they pitch their roles and achievements on Linkedin following time spent at your company. Some stuff is more outright lies than embellishment. When I used to work in IT testing, I had one guy who not only falsely claimed a senior management position but who also had the audacity to claim my achievements for his own.