Not really compared to some western european countries.
Well, when I was 5'6 at some point I considered myself to be short but I grew a bit and at 5'8 I think that I'm about average. I'm 173cm and the average for Polish men in between 20 and 30 years old is about 175cm or so. So a bit less than in Ireland.
Overall average is about 170cm though because females are much shorter. About 90% of them are shorter than me, I'd say

However some Polish people, especially young are very tall. Maybe that's why people think that we're pretty tall. I have a few much taller friends and I guess people like them are rising the average. After all it's easier to be 20cm or so above the average than 20cm below it.
Amongst my closest friends about 1/3 are definitely taller than me, 1/4 are significantly shorter and the rest is about a similar size, with some being maybe a cm or two taller - but I'm not too sure about that. However those "taller" are taller by a much bigger margin than those "shorter" are shorter if you know what I mean, lol.
So yeah, I'm not tall by any means though but I've never heard anyone calling me short except of me myself some years ago. I guess that "barrier" below which someone might be considered to be rather on a short side is somewhere at 5'7 or even 5'6.
I often hear from girls that a guy has to be "above 170cm" to be considered ok lol.
One of my close friends is about 5'4 or even 5'3 and I often hear other of my friends making jokes of him. But it wouldn't be that terrible if he wasn't skinny too.
But back in the days I was also skinny so I could've looked pretty small. I've bulked up a lot since then and I'm pretty much satisfied.
Wow, what a midnight rant, lol.
To be honest though I thought that most people in here were taller for some reason