Well, the country loves him that's why he won.
I don't think that the main reason why he won is because of him making Bitcoin a legal tender. Sure that might affect it as well, but it isn't the main reason.
What will be the effect of this on the whole crypto market? Little to none because TBH, I've seen little to no effect of his decision to make Bitcoin a legal tender to the overall market. Anyway, congratulations to him, and with him getting the majority of the seats, I'm expecting that something that's crypto-related will happen.
Just curious, is there any data that we can see online regarding how much Bitcoin is being used in El Salvador to pay for things? I mean it's a legal tender in that country already right?