But I don't get, there is like no cost in owning a domain. It's just an entry in a DNS server. How is even 10$ justifiable for owning a piece of address as recurring cost?
I find interesting in if Berners-Lee (or whoever) on the invention of the internet had said "I'll own and run the domain registry" they likely could have made themselves the wealthiest person in the work if they wanted.
Given how monopolistic domain registries are and their ability to print money, its going to be an ongoing battle to keep corruption, predatory behaviour and generally lazy excess away.
I bet there's also a non server cost too, though. All I could find is a $0.18 fee to ICANN: https://www.namecheap.com/legal/domains/icann-fee/