"Do you like it?" is about entertainment value and the strength of the story, not the strength of the actual execution. When people say that Jordan is "not a good writer" they usually mean exactly that - he doesn't write well. His story is fun and entertaining, but the actual mechanical execution, from any perspective (style, aesthetic value, word flow, strength of descriptions) is not stellar.

Since, as you noted, people differ in their tastes, a writer who can write well will almost always have supporters, so I don't think your point is really relevant (i.e., that a likable author can be good or bad, but an unlikable one can never be good). You yourself mentioned that likability is a subjective measure, so I can agree with you that the statement you made is true from a subjective perspective, but it doesn't affect the question of whether or not Jordan is a good writer.

I don't think Jordan cared about being a "good writer", though. He had mentioned over and over that the story was the most important point for him. The reason I feel it necessary to even comment in a post like this is because I think it's worthwhile combating two equally absurd viewpoints:

1. Irrational fans. These people think that, because they like the Wheel of Time, this means Jordan is the Charles Dickens, Fyodor Dostoevsky and Gustave Flaubert of the 1990s and 2000s. They try to elevate bad prose to the level of literature worthy of literary analysis and discussion.

2. Cretins. These people intentionally bash good literature because they themselves are incapable of appreciating it, and attempt to say that Jordan is better than traditional literature (in some dim way recognizing that Jordan is somehow "different" from literature as an art form) because they understand or appreciate Jordan but not serious literature.

I realize that neither group is going to be persuaded, the first because they are intentionally blind to criticism and the second because they are ignorant and uncultured, but there are other people who aren't in those categories who will still be swayed by arguments, and it's worth a bit of time to make sure the argument is made.