I was kinda in similar shoes to OP but I am at the start of my career and it became obvious to me that I was not working at the same level as everyone else. I quit because I was severely burnt out and like you, I didn't want to pretend.

9-5 just isn't for me but it seems like you found a way around that with freelancing. I would love to do the same. Can you please shed some light on how you got started with it and how you built you client base?

I have always admired those that get to work in their own time as you do, it would be a dream to do the same.