Yes I agree it's a mental illness. If body dysmorphia is a mental illness then so is being transgender.
This from a journal that actually talks about it being declassified as a mental illness and saying it's not about choice or following fads:
'.......recent studies comparing transgender and cisgender persons show differences in the cerebral networks involved in own body perception in the context of self (Manzouri and Savic 2019; Nota et al. 2017), and in the patterns of brain connectivity that might affect one’s sense of body congruence (Moody et al. 2021). If proven, a biological aetiology would destigmatize transgender behaviour.'
I then googled 'do people with body dysmorphia have differences in the cerebral networks involved in own body perception in the context of self' and google said:
'Yes, individuals with Body Dysmorphic Disorder (BDD) exhibit significant differences in brain structure, function, and connectivity within networks responsible for processing visual information, emotions, and self-representation.'
So if body dysmorphia is a mental illness then surely so must be being transgender.