Well, I don't think I would say anything except, “that's great!”. I didn't think the exam was hard, but I personally wouldn't ever voice that to other people (I do realize the irony here, but I just mean outside of a forum thread on the topic) because you never know what people struggle with on a personal level and my goal (anyone's goal) should never be to belittle someone or make someone feel bad about themselves for the things they struggle with.
For some people, public speaking is a fear worse than death. I'm sure they would want to punch you in the face if you went up to them before they were about to go give a speech to 200 people and said, “Ehh, piece of cake! You'll be fine…nothing easier than talking to a crowd of people!”. Some people are insecure and validate their achievements through other people (i.e., telling you about it and hoping for praise/shock/awe/etc).
I wouldn't pay them too much mind. Whatever their reason, you never know what they struggle with on a personal level that you may take for granted. For example, you may have had an amazing childhood…loving mother, father, happy home, good marriage, the whole nine; whereas, perhaps they came from divorced parents/abusive family, can't find a stable relationship, wife left/took the kids/had an affair, etc. So whenever someone talks smack about the exam and it makes you feel bad about yourself or what you're trying to do, just realize that everyone has their demons and maybe that one shred of glory is how they feign confidence on a daily basis; just shrug it off and think about all the amazing things in your life that might not come easy to other people. Just food for thought; a different perspective perhaps.
In any case, good luck! 🙂
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