No idea where I post this question but im just curious, how are we trading for osrs gold? Doesn't jagex track trades?

Nobody is watching, you have to do some egregious trading on or to a fresh or not played account.
Or the person you are trading has to report themselves and you after trading, and jagex has to follow up on the report (Not guaranteed)

ive done numerous gold trades throughout the years totaling over 30b and i was never banned, i think if you have an "old" account you stand a best chance to go undetected