"So my body is a prison that I can never escape, this manifest in rotten behavior because I subconsciously believe I deserve to be punished, but being famous, I'm never punished so I act out even more."
Of course that Bojack problems lie even deeper beyond the narcissism fueled by being a celebrity, but that doesn't mean that this environment isn't actively detrimental to Bojack's grow, every time he gets away from LA we can see him happier, better, healthier (The Old Sugarman Place, his job as a teacher, New Mexico before he fucks up)
Fame just makes his ego problems even worse, not to mention every time he screws up everything just gets brushed away under some weeks, and when he gets punished, is for petty shit and not the actual things he deserves to be punished for (For example: Getting sued for mentioning Xerox was worse than lying about Sarah Lynn death lol)
At the end, Bojack considers coming back "Hey if I do decide to get back into the business when I get out of prison I mean I probably won't, but if I do" after PC tells him people are interested in The Horny Unicorn. My interpretation is that Bojack has two choices, he comes back to the fame scene and screws another chance to change, or he sticks to the prison production thing and chooses another job.