It's a cultural thing. The cultural norm in academic or technical circles is extreme precision as well as fear of being held to account by enforcers of that norm. It's a spillover of rigorous academic publishing norms into general conversation. It's a fool's errand given that speech is intrinsically imprecise, and given that everyday speech is just a communication tool and not a vehicle for perfect applied epistemology.

We should hedge statements depending on whether the context makes it self-explanatory that there's uncertainty. Any less, and we're being deceptive. Any more, and we're adding words without adding information.

You know what would be a cool? Some notation to denote the level of certainty that doesn't take up horizontal space in the sentence. Or an API to a fine tuned GPT-3 that can strip out caveats and hedges from text on a screen.