well, thankfully i don't think it's possible to 100% agree on anything or else we would be the same person! but, i do want to continue to challenge some of your assumptions

First, in my impression of it, even bourgeois science does not think it is immutable

see, but the example i provided you of the neurobiology of bipolar disorder clearly and directly demonstrates bourgeois psychiatry's view that the brain is immutable. the fact of emotional dysregulation in bipolar is in interpreted as though the patient was necessarily born with this brain abnormality, and furthermore that this brain abnormality will necessarily persist for the entirety of the patient's life, i.e. that it is immutable. again, this flies in the fact of neuroplasticity, i.e. the fact that our experiences in life literally change the physical structures of the brain. why isn't there, for example, longitudinal research that finds those with a high risk of developing bipolar at a young age (whether as dictated by genes, material circumstance, or both), conducts regular brain scans to check the development of the brain, and correlates differences in development with differences in experiences of the patients? this is just one example, and it's not like i'm a scientist or a researcher, but in my research i've found no such studies conducted, because the brain is seen as a mechanistic machine.

but rather liberalism and individualism blanch at the idea of forcing someone to “not be themself” in matters of personality and the like.

this is an interesting idea, but is this actually supported by the way that those with neurodivergence, disability and extreme mental disorders are typically treated under liberal societies? i certainly don't think so, even though this is a claim that liberalism constantly makes. disability is literally the extent to which those different from the norm (for a variety of reasons) are excluded from society. those who experience things that are outside the realm of "normal" or "rational" are not accepted but controlled by liberal society. the way in which medication treats symptoms (often poorly) instead of underlying problems (brain structure) is itself a rejection of neurodivergence imo: people are reigned in from their extreme experience instead of being prompted to explore it and identify why they experienced something in the first place. i'm not saying there's absolutely no place for medication, but in bourgeois psychiatry it is seen as a long-term solution instead of a tool to help facilitate actual healing and brain development.

That said, the reason I used ADHD as an example is because the research makes me doubtful that an ADHD person can simply apply therapy tactics and “fix” their brain.

exactly what research gives you this impression and why? i've honestly done very little research so far, but have found several examples of people with conditions that are typically considered permanent fully recovering.

i think it makes sense for you to have reticence towards the liberal anti-psychiatry movement, in that it totally rejects everything in liberal psychiatry and is therefore open towards eugenicist claims towards those with autism, for example. but, i think the way in which those with disability and neurodivergence are treated under liberal society have much the same problem: leaving those on the fringes with at best extreme hardship and at worst death is eugenicist to me too. furthermore, i don't claim that all examples of permanent neurodivergence as dictated by liberal psychiatry are actually impermanent and treatable, just that some are. and, the only way to actually distinguish that difference is to conduct socialist research that bourgeois psychiatry is incapable of conducting.