heiwuchang

My chemistry teacher mentioned that the acidity of HX compounds increases down the group (i.e. HF<HCl<HBr<HI), and I get why it is so (because the atomic radius of the atom increases down the group => bond length increases => less attraction between H+ and X- => donates H+ more readily). But whenever I search for strong acids online, they only mention HF and HCl, while HI is very much stronger than those acids. Why is it like that? Is it just because they are more well known? Or is there another reason?