A big part of the problem with Wick's article is his (re-)definition of the term "roleplaying". If a game has some method in its rules whereby one can create a customized in-game character, a role, to play, then it's a roleplaying game. (Cue several examples of RPGs where creating customized characters isn't possible.) That's the meaning of the terminology as it was first defined. Calling the game that engendered that definition "not a roleplaying game" is ridiculous twisting of words. Unless your intent is to generate a lot of useless arguing over semantics, you don't get to redefine a term in use for 40 years. Use different words.
Yup.
Games called RPGs tend to have one or more (but most times not all) of these traits:
player controls just one character
the character performs a role on a team (Fighter, Tank, Wizard) with a specific skill set
the character advances is proficiency and the player makes choices about what skill areas to improve, at the expense of others
the character may be portrayed by the player as having a specific personality and behavior pattern (aka Role Playing)
I doubt my list is definitive nor entirely correct, but those are the most obvious things I see in most things called an RPG, be it table top or computer. Some games let you control multiple characters. Some games don't have any kind of advancement for the character, but I suspect that is more rare in the category.
One thing I left out is Story. I suspect just about every CRPG tells a Story (ex. Final Fantasy, Elder Scrolls, etc). Straight sandbox dungeon crawling might not tell a Story, except in the crudest sense of linearly describing what happened to the PCs.
Since Wick's article was really getting down to "RPGs must tell a story" is that part of the conflict? Given that I see valid point to not require "Story" as part of the traits of an RPG.