It's possible to tick all the boxes you list and be in utterly selfish, emotionally immature, superficial, materialistic knob who scares along on the surface of life caring about nobody but those whose achievement reflects on them.
Ah yes BlueSkies I know exactly the type you speak of! The one in particular that I have in mind has acquired all her ‘grown up’ wealth from daddy... i don’t think she’s ever done more than a few months work at a time in her life! Totally flaky, non committal, only friends with people that benefit her or reflect well upon her. On the outside she has such a grown up life owning several houses, kids in boarding school etc yet all she has won is the birth lottery! That’s not being grown up to me.
Similarly I actually do know several couple one in particular who tick all those boxes and they are a little ... erm ... retentive and holier than though (think Dave and Sam Cam types
)
Op seriously don’t sweat this pressure to be ‘grown up’. It’s not actually about having money or looking polished. To me being a grown up is:
Taking responsibilty for your actions (did David Cameron manage that over Brexit?)
Knowing when to put your selfish needs first
Working hard and making a difference (applies to all jobs from PM to SAHM)
Knowing who you are and being true to yourself. NOT aspiring to being a certain class or being seen as a certain stereotype, just knowing who you are and being quietly fine with that.
Admitting your faults
Being loyal, trustworthy and staunch in your relationships with all