The fact that the survival rate of startups hasn't improved doesn't show that our knowledge hasn't improved. Startups are competitive, with only 1 or 2 VC-scale winners per market. So, the claim is like "race car technology hasn't gotten better, because there's still only one winner per race."

The Lean Startup methodology is likely applicable only within a very narrow niche: a newly discovered green field with plenty of low-hanging fruit. Web apps in the late 90s and 2000s. Mobile apps after that. Agent integrations now. These are areas where the barrier to entry is low, problems are plenty, and there's space for a thousand flowers to bloom.

In contrast, for a company that can't be started by a single app developer - getting out of the building won't help. Nobody in the space worth talking to will talk to you, for starters.