His money? You mean money he got in loans in the name of his investors!
If MicroStrategy goes down it's not Saylor who will be going to be the one counting the losses it's the guys who loaned MS money and the guys who invested in that company, it's the same with Bukele, he didn't buy coins for Salvador from his pocket, he used government funds, aka people's money to do it. It's pretty easy to be bullish and not care about the price drop when it's actually not your money at stake.
If you print money or shares and you don't care about them as long as you get $ which you can use however you want it's pretty easy to ignore that, how many times have we seen companies issuing shares after shares, getting tons of investors money and then delivering nothing with anybody facing any punishment for that? Look at what Faraday Future has done to billions in investments and despite losing all the money the next month they got another one and lost that money again and so on for 7 years in a row. And despite that, they still got listed on NASDAQ where their shares are down 92% to date.