I haven't even heard of Instagram before their change in ToS.
Seriously??? That's very surprising that someone who reads hn hasn't heard of something as popular as instagram. It was a big deal on hn when fb bought them. even a quick search on hn shows over four thousand results. I don't buy it unless you're new to hn or the internet.
The person you are replying to has 12 karma. They may very well be a rare browser of HN and tech-sites in general.
I've only been reading HN constantly in the last two months and some sub reddits like /r/linux /r/programming and /r/cpp.
To me HN is just a ripoff of Reddit.
Absolutely. The people who'd get up in arms about the whole thing likely weren't users in the first place. I told a non-HN-reading, Instagram-using friend (i.e. an average American college student) about the ToS fiasco the other day; said friend frankly did not care a bit, and wondered why anyone would.