@Md. Salim
Thank you for this insight but it remains hard (in my head) what to use first.
A thought: If I enter a website and I want to go on vacation as a single traveller, maybe I mihht be interested in the offerings only for my age group. I could use type of vacation but I am not interested in all vacations that are not for my age group.
For this reason it sticks in my head to mekae age-groups a category.
If I use age group as vategory, the chain of thought could be:
Give me all vacations for my age group, skiing, France, January,…
I understand your pov but I am struggling ??