Because a lot of people haven’t heard of it: amatonormativity describes the way society expects everyone to want a relationship and prioritise romance/starting a family and having kids over other things in their life. Aro or not, you have likely come across this sentiment in your life.
Examples of amatonormativity include: parents who think you owe them grandchildren, co-workers and friends asking why you’re single/not believing it’s by choice, the idea that you’ll “change your mind” about having kids when you “find the one”.