Without specifying which (other) enemy fighters the author is talking about, mentioning F-35B and J-15B in the same sentence when talking about "competitive in battles to control air and sea" means they are being compared to each other; this is the most natural interpretation of the sentence, and you would have to do some intellectual twisting to interpret it otherwise.
I would argue that interpreting illogical statements (some of which may be inaccurately translated or even inaccurately transcribed if it is written by someone unfamiliar with military matters) in a manner that makes sense if it is from someone with a more official military background (like a RADM Yin Zhuo) is justified.
In this case, I sincerely doubt Yin Zhuo would say that J-15B is as capable as F-35/B in a general manner given his level of competency, so either he said exactly what was written in the article and he meant it in the manner that you interpreted it as (which would reflect poorly on his competency and which I think is the more unrealistic option), or the alternative is that his statement was misinterpreted or taken liberties with by the writer of this article and written in an inaccurate way (where the fault would be with the writer of the article).... or the third option which is also possible is that the Rear Admiral was just deliberately BSing.
Or in other words -- sometimes intellectual twisting is sensible.