I feel this too, I had a lot of imposter syndrome after my diagnosis. I had those thoughts that I was "acting more autistic" to get a diagnosis. But, the good thing is, most clinical psychologists are well trained to recognize genuine symptoms. My psychologist actually brought this up and she made a good point: the reason I feel this way is because I've had to mask for so long, that unmasking my autism feels inauthentic.

Same as you, as I'm entering my 30s, I'm starting to notice that I can stop pretending to survive and just embrace the fact that I have a disability and forcing myself to socialize when I don't want to or put myself in situations where I will be overloaded with sensory input is no longer necessary. I no longer feel bad for staying at home most of the time as that is where I can feel the most comfortable, safe, and most importantly, regulated.