Normally if we want to ask someone what they find difficult about something (learning to drive, speaking a language), we would say, "what's hard about..." or "What do you find hard about..." When you hear "What's SO hard about..." It is usually because one person says "X is hard." And another asks for specifics. Example. A: I'm having so much difficulty understanding English programs on Netflix. B. What's so hard about it? A. Well, first of all, the people speak SO fast! It could also be that the second speaker doesn't think X is hard. A. (Learning how to drive a stick-shift car). I just can't do it!! B. What's so hard?! You just put your foot down while you switch gears. No problem. A. Easy for you to say! Every time I try, the car jumps and stalls.

"Why is it so difficult?" "What's so hard about learning English?" "What's so hard about reading every day?"

Thanks

You could. However, it would be more usual to say: - Why don't / can't you get it! - Why are you finding this so hard/confusing - Why can't you understand All of these are a little bit confrontational though. You would say them if you were a bit exasperated. A nicer way would be: - How can I help you understand? - What don't you understand about it?

Can I say this? "What's so hard about understanding/getting it?"