@andyis, pardon me if I got your question wrong. I am huge fan of doing things I like. So if you think IMO what you would enjoy doing, go for it and take a gap year. If you get a medal, that would be a boost. I personally took a gap year partly because I enjoy programming and wanted to participate in the National Olympiad in Informatics in Russia for the last time, to get the vibe of coding four tasks in five hours. I had a dream of attending IOI but I was pretty realist to know that there were people who dedicate way more time to programming and are more proficient. But I did score high enough to become a prizewinner which definitely boosted my application. So again, if you enjoy Math enough to work hard for IMO, it is the chance you can’t waste. By the way, during the gap year, you can learn more about real life which also helps at college. I am a gap year supporter no matter the reason. My gap year was just the best decision I made in my short life so far.