Originally posted by Class A Oh, no, please!
To be fair, his message is to stop arguing and just use what you want because the technology is sufficiently advanced that they're all good. (Subject to how much you pay, I guess.) So his arguments are a little flawed. That doesn't change the message.
It's what most people do anyway. A friend has just changed from a Nikon D5100 to an Olympus OM-D E-M10, so from an APS-C to Micro 4/3. She's no professional, rather, an enthusiastic amateur and she gets better pictures with the Olympus than the Nikon. Why? Lots of reasons, including specific performance on various factors, but mostly size – she picks it up and carries it more often. Instead of a camera bag she now has a shaving kit bag.
So a FF is better than APS-C if you want a FF more than APS-C. In my friend's case, Micro 4/3 is better than APS-C. For many people a mobile phone is better than APS-C. For me, I don't want to lose my (currently) 450mm equivalent focal length, so FF is worse (leaving aside the fact it's a DA lens). Then again, if a FF had the same density of pixels it wouldn't matter.
All technicalities – so back to the message. Choose your mount and enjoy it.