A marketing startup went from 70% close rate to 20% because of Claude. What might've gone wrong???

A startup went from 70% close rate to 20%. Not because their product was bad or competitors out-executed them. It's because Anthropic shipped a single feature. And now, the question needs to be asked. How many products being built right now are just gaps that are to be closed very soon by someone big? And has the old playbook ("find a gap, fill it, scale it") became the most dangerous advice a founder can follow today? I'm genuinely curious, what's your read on this?