I haven't interviewed for a job in many years, but on a whim, I decided to pursue a new role. I made it to the final interview with senior executives and was expectedly grilled about my qualifications. During the interview, I described several projects I worked on from start to finish, covering all stages such as gathering requirements and architecture. However, I received feedback that it seemed I had taken on too much responsibility, making them unsure of how much I actually contributed. Yes, totally agreed.

That was just the stated feedback. They just didn't like you, and found a reason not to. This effect is well studied.

The better you understand this, the more it won't make a difference, sadly. At least you can get through the rest of the week though.