Someone asked a really good question on Ask and Answer...

My favorite thing about getting older is I can say or think "I don't really care" and totally mean it.

The time to discover. Learn more. Whether it be history, nature (birds), how to crochet, a new language, whatever strikes my fancy.
And I'll echo no more periods. Mine stopped after chemo, when I was forty. But I could throw a ticker tape parade every day over that one alone!

I finally know who I am, and because I know this, I am comfortable with myself and my life decisions, which are dictated by me, not other people.
Also,I have more daily awareness that time is finite and so I say what needs to be said and do what needs to be done.

Not being tied to kids school and extracurricular schedules is a huge one for me.

Having a little wisdom that comes with age and experience.

Today is the first day of school for my district (teachers started two weeks before the kids). I retired at 50. I do miss the kids, but I volunteer at the school once a week to get my kid fix. I love not waking up to an alarm clock.

I guess just knowing myself better and being a more compassionate person toward myself and others.

Not caring as much what other people think of me and not feeling the need to go along with the crowd. No is much easier to say now.

Having the financial freedom to do what we want (for the most part).

No periods. I haven't had one in 13 years. I was recently with some friends and one of them is much younger. She was worried about being at the pool and having her period. I had to laugh to myself because I haven't thought about that in years and it took me a second to even get what she was talking about.

Wisdom, as in discernment based on years of lessons learned and experience.

Appreciation of stuff I used to take for granted.

Understanding my own strength, abilities and value.

Being retired and having lots of free time.

They're my thoughts too 

And we love being empty nesters (do I need a different phrase since it's been about 4 years since our youngest left home?) 

i'm 53.  my favorite thing is just being alive.  i am at that age where some people my age are starting to get cancer or some other serious illness.  some of my friends have even died already.  unlike my 20's, i know i won't live forever.  i'm just happy to be alive.

The best thing about getting older is being one day closer to retirement.

Honestly? What honestly comes to mind?
Not teaching or having children in school during a global pandemic. 

For me, it's been figuring out who I truly am.
It didn't happen until later  in my life (40's and 50's). Better late, than never!

I took me a lot of healing, then a lot of soul searching....to figure myself out.
I spent far too long in my younger years being controlled by someone, being who and what I was expected to be, being who I thought I was supposed to be, etc... Being someone other than who I truly was.

At the age of almost 54, I moved into a studio apt all by myself. In general, first time living alone (other than three months by myself, getting away from ex-husband) but that was stressful, I was broke-no money, I was broken(emotionally), and I was being stalked by ex-husband........so it wasn't single girl, cute place, fun. It sucked!

This past couple years in my own little place have been life changing for me.
The freedom I have felt is indescribable. I can decorate however I want. I come and go as I please. I am in charge of my money. If I don't want to do something I don't do it.
I drove myself on a few days at the beach road trip by myself in 2018 (I'm a big girl now!).

My 50's have been the best years of my life (minus the pandemic and being mandatory out of work for a couple months). 

The other best thing of my 50's >>>> No more period! No more cramps! No more (TMI >>) "peri-menopause heavy flood, that would arrive whenever"!