Tomatoes are not generally considered culinary fruits, so there is, in fact, a sense of "fruit" on which tomatoes are not fruits. They are biological fruits, which is what someone who invokes a "technical" sense likely means.
Yeah. For some reason some people seem to think that some contexts are superior to others just because the context concerns the scientific background, even though everyone has a prior conext in mind which is the social default.
In a precise language it is obviously utterly useless to have homonyms that are not just distinct but opposed in meaning, unless one is the inferior. Of course that depends on context, because language is inherently underspecified (i think), but i like to think that the acclaim of is the more general, here, whereas cooking actually isn't predominantly concerned with names.