Deciding between Business or IT for my education. Should I place more importance on what I'm interested in? Or which one will eventually draw more income?

Can go networking session, go talk to those already working in IT and business, see what's their day to day is like. If you can intern for it might be even better to get some feels on how is it like.
Most of the time, what we study and expect the situation is at work is different. If you could intern for some of it, then the experience on working at the job would give you a sense of day to day light. What I'm trying to say is that, even study in Business is what you may prefer for, but the work might or might not be what you like. Same for IT.

Finally, I would choose IT ($ ) over Business because I've tried both even though I'm from IT. I've switched to Business lately but still didn't really like it after a year of working on it... though it gives me more $ ..I still find daily I'm missing what I love to do most in IT, or development / UI /UX. After some soul searching, I decided to go back to IT because that's what I love to do most despite that the business position that i"m working on provides more $.. .but daily is a chores living /doing things that I find no passion on and it felt depressing.
So go for what you love as long as you make sure the pathway to upgrade is providing enough for now and the future. Most of all, keep life simple so that $ doesn't become a driving for what you choose to do day to day.
Not many gets to F.I.R.E early, thus we gonna work at least for 30 to 40 years +/-. So

Do what you love, love what you do.
Hope it provides a different perspective. All the best!

I would choose IT first, then do a Masters in Business. This way, you can draw a higher salary in your younger years. If you invest properly, you'll be able to enjoy when you're older :)