Ask HN: How much would it cost to own and operate a personal gTLD?

I've briefly looked into it before, but the discussion here [1] earlier today made me curious again:

How much would it cost to own and operate a personal gTLD? Say, `.gabriel`.

ChatGPT claims $250k to start then $100k per year. Is this reasonable? Completely off?

[1] https://news.ycombinator.com/item?id=45068215