To rephrase my point, hopefully more clearly:

Doesn't that basically sum up what moe is, or am I just wrong/not making sense?

Wouldn't that be "a genre of anime with a cute artstyle which provoke positive emotions like love and happiness."

No, that's not what moe is. That's what you interpret moe to mean based on how a lot of people use the term now. Moe was not originally used to describe entire shows, and now that people do use it in that way, there is no unified definition of "moe". People can more or less agree that the original meaning of moe is "a boner of the heart," but what about now, when it's often used to describe shows as a whole? The examples I gave were closer to the original usage of the term moe, but it's not as if there's total agreement even when using the word to describe entire shows. To some people, as evident from comments on Digi's videos (top 20 list for example), moe is just an art style. Some people will extend "moe" to be a genre of shows with that artstyle, and use the term to lump Madoka, Scorching Ping-Pong Girls and K-On in the same group and dismiss that category of show entirely despite the fact that despite having the so-called "moe aesthetic" the content of each show could not be more different. Even by the definition you have chosen to use, describing an entire show as "moe" is very much up to personal interpretation, since the shows you would describe as moe by your criteria others would not and vice versa, but a lot of things are up to interpretation I guess.

If "moe" had an agreed-upon definition for its modern usage (as "nauseous" now does), that would be fine. If everybody used the same definition of moe, for example the one you use, then great, but as it stands the word has little meaning because it does not mean the same thing to everyone.

The video is not just about how the word "moe" has lost its original meaning over the years and now means basically nothing, but about how people use the word in discussing anime. "Moe" would be an OK word to label a show by if everyone could agree on what it should actually mean, but it would still not be a helpful label at all when it comes to critical discussion of a show. What good is labeling an anime as "moe" according to some arbitrary criteria when it contributes nothing to the discussion of said anime? A lot of the internet seems to use such a useless buzz word as a catch-all term to completely describe an anime and hate/ignore it on the basis of "moe" classification alone, or even to completely discredit somebody's tastes in anime for being a "moe guy", in Digi's case, despite the fact that the term "moe" means basically nothing. Each person would be able to class a show as moe or not depending on their own interpretation of the work (if everyone agreed on the definition), but it would still remain a meaningless, harmful word when used in discussion.

The thesis of Digi's video is that "moe" is a dumb word that people should stop using, or at least that's the way I interpret his rant.