Was reading an anecdote of an acquaintance's nontechnical friend getting horribly hacked and losing big money. Ugh.

So I was checking the basics of our home network setup and noticed that on my Ventura MacBook Pro, the firewall was off, all connections allowed. ?!?!?

This suggests that's the default: https://support.apple.com/en-ca/guide/mac-help/mh11783/mac

Um… you might want to check?