This sounds a bit like the fallacy of the beard; the existence of ambiguous behaviours that exist somewhere on the spectrum between "listening to an entire podcast with ads" and "automatically downloading the podcast, editing out the ads, and reuploading to a personal RSS feed so you can listen to it ad-free" shouldn't prevent us from contrasting the behaviours at the extreme ends of the spectrum.

That said, "unethical" was clearly a poor choice of words, as that's quite a loaded term. However, this technology is designed to systematically circumvent the mechanism by which many podcast creators earn money for their effort, and even if "unethical" is the wrong word, we should still discuss whether putting these technologies out, and using them, is a good move - particularly if we care about rewarding creators and supporting the podcasting industry. (And there's an argument that goes even further, around whether doing something like this is systematically violating an implicit contract with creators, even if it's more of a moral contract than a legal one).