It's actually a very interestingly shaped graph.
A lop sided bell curve.
Gradually increasing up to age 55, then more rapidly decreasing after 55.
I suppose it makes sense.
Youngsters/young adults are more likely to be on tik tok, in the pub or looking after young children.
50 - 59 year olds... I'm not sure about why this is highest. I can only say for myself (age 52) why.
I have more spare time now as my son is a teenager and I've dropped to a 4 day week.
I find it interesting, and want to keep up with new ideas/changes.
I like the social interaction.
Then, I guess, as you get over 60 you are more likely to be retired, perhaps more illnesses, maybe.. more time with grandchildren! Actually, I'd like to think life kicks in again and you oldies are doing lots of fun things now you no longer work or look after children!