IARC's piece in this puzzle is to aggregate research showing something is a carcinogen, but this includes a lot of things that are harmless or even healthy in low doses. Sunlight, for instance, is obviously a carcinogen, but the amount of exposure you want is not zero. X-rays can cause cancer, but the optimal lifetime exposure to x-rays is not zero. Once IARC classifies these things, the purpose is to recommend to other researchers to now go look into these to find dose/response curves in animal to see what a safe and unsafe level actually is.
As far as the EPA has been able to tell, glyphosate at the level any human would ever get exposed to from its use as a pesticide, is safe, even though it's a carcinogen. Think of like being in the same city as smokers exposes you to cigarette smoke in the shared air, but at levels nowhere near enough to meaningfully raise your cancer risk in spite of the fact you're regularly breathing in carcinogens. Living in the same room with a smoker is a lot worse. Actually smoking is even worse than that. Probably don't drink straight glyphosate on a regular basis.
Similarly, you don't want to drink bleach, but cleaning your counter with bleach and then eating off of it is not only perfectly safe, but arguably even better than just eating off the counter beforehand, because bleach disinfects it.