Your entire argument seems to be predicated on this idea. But the thing is, pretty much every linguist in the world would disagree with the notion. The connotations of words are constantly shifting — there is ample evidence of this throughout the history of languages.

I applaud you for thinking about this sort of thing and speaking out about it, but in this particular case I think you're tilting at windmills.

Even if we accepted this absolutist stance where words' meanings do not change no matter what the common perception or intent of the speaker might be, it still wouldn't be offensive to women. If the word's connotation is immutable, then it does not refer to human women at all, but to dogs, and thus human men have just as much right to the word as human women do. But surely you'd agree the word has acquired new connotations since then, contrary to your claim above.

There might have been some point in history at which your stance was the right one, but if there was, I think that time is long gone. I don't know if you're just that old or if your regional dialect is odd in this regard, but I'm pretty sure the verb "bitch" is not gendered in most people's mental lexicons today. Because it is not particularly associated with them, it does not actually do any harm to women as a group if you use it.

(Note that all this is distinct from the noun "bitch," which is applied to men but is still has gendered associations. Probably best to avoid that one. And obviously avoid both in formal contexts.)

Bitch please!

For instance, you say "normalization that's designed to subordinate" -- 'designed,' eh? By whom?

You also state "by repeating it, that is the sentiment you are reinforcing," but I find the justification given confused and weak ('because the meaning does not change').

You also mention a common cultural trend: the notion that words originally applied negatively to groups can be appropriated for positive use by others. But instead analyzing this mechanism, you just blanket-assert that the negative words are the property of the slurred group and that others are, in general, not allowed to use those words.

I don't think most people here would state "I'll use derogatory word X all I want," and I think you're spot-on about the origins of the expression in this case, but this particular post smelled fishy for some reason.