Brain will repair and reconnect itself through neutral “rerouting”.
This happens in the first 6 months, maybe a year. Not much happens after that, though the brain can still "adjust" for years - they said that most of what comes after is negative :D
There does seem to be a collective situation - a kind of "giving up" feeling. It might just be that it is the end of a long year and people are getting the feeling that 2023 isn't going to be any better.