Around 2009ish, I had a coworker who swore anything over 16 bits wasn't embedded. We were working on a MMU-less uClinux ARM7 system with 16mb of RAM and no networking and that didn't meet his criteria for "true embedded".
The next job I had was a piece of customer premises equipment that ran a fairly high powered ARM board with dual gigabit ethernet links and a lot of user space written in PHP. No one on that team questioned that it was an embedded system.
It always seemed like a strange thing to gatekeep on. Personally, I base my definition more on the use case than the power of the machine.
When I were a lad, if you had more than a dozen bytes of RAM it wasn't REAL embedded. /shakes-cane
I generally use your definition, though. Any computer that the end user doesn't think of as a computer (and isn't expected to maintain or directly use) is embedded, whether it's a camera with touchscreen GUI or an ABS processor in a car.