I've seen something said several times which annoys me.
"No non-native speaker will ever learn Polish to the level I do - a native Polish speaker. Therefore, Polish is extremely difficult and beyond the abilities of most people" It's perhaps the most arrogant thing I've heard for a long time.
I'm a native English speaker and I've never, ever, met any non-native who speaks English with the fluidity and ease which I do. I've heard them speak well, but not like I do, and there are people with a far greater command of it than me (writers, poets, academics, etc). That means that English is super complex?
I really enjoy Polish and hope that when I get to learn it, Polish speakers don't try to discourage me by saying "it's too hard for you - don't bother". If more Polish speakers supported learners, you'd find the levels of proficiency rise. I'll master the language, I promise you that!
By the way, in the overall scheme of things, in the complexity of languages overall, Polish is merely moderately complex. There are things which would blow a Polish speaker's mind. haha