TBH, I don't even get why the TFA author's idea was necessary. The US Constitution was built out of a long series of debates, compromises, and not a little effort towards future-proofing (and let's be honest, idiot-proofing). That, and they included mechanisms to modify it as needed.
Sure, the process was arduous and it involved a lot of potential inclusions that would quite frankly scare many folks today. That said, once finalized and ratified, it's in place and should be treated as the original document. If you (or anyone) want it changed, then use the mechanisms included to do just that. We've managed to do so for a couple of centuries now without violating the thing, so why get all creative about it now?
The complaints: It's too hard to get 66% of Congress and 75% of the States to agree to change it, so politically it's just easier to get SCOTUS to allow the Federal government to do what is desired by "reinterpreting" the meaning you want into what was already written.
It's primarily a complaint by those in favor of Big Government; though many in favor of Small Government have turned to it as well in order to try to roll back the Progressive movements of the last 100 years. So both sides are now guilty of it.
There's a balance to be struck between the two positions; though I do favor the Originalism position more and give more weight to it. There's a lot to be learned from history and Originalism forces you to look back at history, learn from it, and apply it to today. The "Living Document" position does not, and sets up the repetition of history as a result since they ignore history, ignore lessons learned from history, and just try to do their own thing.