I've mined before and this isn't how it works. I was mining dogecoin in 2014 or so (before Elon hyped it and it was just a joke). You join a "mining pool" where a bunch of people group their processing power together. It keeps track of how much processing each member contributes, and when the mining pool group is awarded a block then it's split up proportionally based on each member's contribution.

Clearly that was a while ago so I'm a little out of the loop and there might be new developments. And if someone had enough processing power conceivably they could go it alone, but I'm not sure how prevalent it is. Probably not enough for an Airbnb miner.

As far as how profitable it is, I would bet that $100k figure is pretty inaccurate. It was a while ago but when I was mining I was tracking my electricity costs vs the value of the coins I had mined and it didn't last more than a few months. It no longer made sense because the "mining difficulty" went up, which meant power cost too much. So it's not entirely easy money, you need to minimize your electric costs as much as possible, as well as cost of your mining equipment.

Miners will buy dedicated hardware made specifically for mining crypto so their margins may be better, but $100k even assuming no power costs and renting an Airbnb seems very high.