You might be wondering: why choose a dot-com domain for a personal website? Well, simple answer: it was the cheapest free option. You are free to choose, and .com is a well-known and established TLD.
I think most people are not familiar with the subtle differences in meaning between the different TLDs.
I bet most people probably have no clue that “.io” is a TLD for the British Indian Ocean Territory and will disappear according to the rules. And I bet some people who spent quite a bit of money for a “cool domain” feel a bit silly now.
So, dot-com sounds like a safe bet, is well known, and also not too expensive. I think that is a good deal!