Yeah I think this is a great mental framework. Getting rejected hurts, it's natural to want to find a reason, and with some self-reflection it definitely can help one grow. But you gotta be very careful about over-indexing on any one interview where the reasons for rejection may or may not have anything to do with what you did and said during the interview (let alone your personhood).
Frankly, if you want to get better at interviewing, it's better to do more general research on what hiring managers and companies want, and then do more interviews to practice communicating that you have the skills and temperament to deliver value.
One specific piece of advice to the OA: this kind of post might feel cathartic, but it doesn't get you closer to your goal. Sure, it will resonate, people will commiserate, and you'll get some dopamine and internet points—but if your goal is to work at a top tier company like Anthropic then such a post can only hurt you. The reality in fast-growing, ambitious companies at the forefront of the AI bubble is that expectations are sky high, and getting things done to attempt to meet those expectations is incredibly difficult for a hundred different reasons. In this type of environment, whatever technical skills you have are not enough. To be successful you need a sustained and resourceful effort to solve whatever problems come your way. One of the most toxic traits is having a victim mentality. Unfortunately it's a common affliction due to the low agency that individuals have in big companies and late stage capitalism in general, but you've got to tamp it down and focus on what you can control (which in practice is often more than you might think). While this post doesn't directly demonstrate a victim mentality, it suggests internalizing the rejection ("My best wasn't good enough. I'm not good enough.") in a way that is adjacent and something that would give me significant pause if I was a hiring manager evaluating for a role in a chaotic company.