In my experience, one's behavior is heavily influenced by neurochemistry, genetics, and upbringing. Neuroplasticity tends to diminish with age... it doesn't go away... but if you are 5 years old, it's significantly enhanced as compared to when you are 25, 45, or 65.
As an adult... and especially now, as an "older" adult... I really struggle with changing behaviors. It's rare that something effects my life in such a meaningful way that it causes a change in thoughts and behaviors.
At some point and at some level, intellectually, I understand what I "should" be doing. The reality is that if a certain behavior requires "conscious effort"... my mental stamina just isn't there to keep doing it. I can do some "low-moderate" masking... but that higher level masking, the type that goes against my nature and personality... I can do it for an hour or two, but that's it.
Pick your battles. Sometimes trying "too hard" has diminishing returns.