None of these concerns seem very specific to AI startups (*).

Like the defensibility and competitive advantage: These concerns exist with most (all?) non-AI startups as well, and they are equally valid. See countless examples of incumbents cloning startups, and using distribution advantage and what's effectively dumping to crush the competition.

(*) Interestingly, prompting ChatGPT with the article title & sub-titles produces almost the same kind of content.