It's funny how hoplites with a giant spear have no problem stabbing someone in facehug range, but try that with a short sword, and it'll just glance.
You know why they have no problem doing it? Because they practiced it, extensively. If they can't do it they are quite fucked. It is not half as easy as it looks, it requires you to look up and then stab down, greatly reducing your vision and aim. It is hardly like all the hoplites can do it consistently, I see loads of them that do not even try.
Now I tell you that 1h stab works fine up close, if you glance, try harder. The age old technique of starting it next to the target and turning it inwards works fine, even for 1h. In fact it is possible to do it sideways due to way higher turnrates, instead of the quirky up down method, which makes it way more usable. The only reason you think it glances, is because it is not a necessity for you to learn it, because you can fall back on leftswings. Hoplites do not have that luxury, so they spent time refining their stabbing technique. If you could be arsed to do the same with your 1h I think you'll be quite surprised.