Why is it a good idea to teach chess in schools?

What are the advantages of teaching chess at schools?

That depends. If you like chess, the advantage of having chess classes for free from good teachers (assuming they are good) is that you play your favourite game / learn something you like / have people to play with / all of this is free. It is really good for average chess players (who will be able to find steady income by teaching others).

But knowing this you have to understand that there are people who do not like chess. How will you feel if right now you will be forced to learn how to play the triangle (kind of funny musical instrument that I by myself find kind of lame). What would you think if your child instead of math/biology/whatever subject you find important would be wasting his time learning triangle/chess which in my opinion will not help his career (assuming he will not become pro triangle / chess player)?

Also forcing a child to do something is not a good way for him to like this something. I enjoy playing chess, but if when I was child I would be forced to go study chess - most probably I would hate this game. There are a lot of places for a person to play chess in his free time enjoying it, so why spoil the fun with compulsory things?

What "life skills" will the students learn by learning chess

What life skills will you gain by swimming / playing the triangle? You will not drown fast in case of flood. You will become a good swimmer. You will learn how to play the triangle and will be able to properly hear/understand music. People can argue that music will make you a better person, swimming will make you more fit, organized, but I am not aware of the proper studies conducted. What skills will you gain by training to solve IQ tests every day? Will you perform well in physics, economy, history, programming? Highly doubtful, and average person who spends 1/10 of your time learning one of these things will perform better. IQ tests will make you a better IQ test solver.

The same way with chess - by learning chess you will learn how to play chess, maybe will learn abstract thinking, thinking ahead and analyzing your options.

I by myself was speaking with some of the top 200 grandmasters and based on their discussion, chess is hard to make money on. You spend thousands of hours on learning preparation, dedication to mastery. And if you are not in top 20 it is really hard to get normal money out of it. Yes, you can publish books, create videos, participate in paid tournaments (which requires a lot of time and effort), but after this amount of time spent in economy you can secure a steady good income.