Here's the difference:
It might be a hassle, but I know it's something that's important to people I care about, so I'm going to change my behavior to make them more comfortable.
Your entrance to this subject was through people you care about, expressing an opinion about something that mattered to them. My entrance to this subject was the fact that as a straight white male, the Internet is either telling me I'm wrong about something or reinforcing the fact that I'm god's gift to this earth and all other races, creeds, and genders must bow before me. As the latter position can be dismissed (with prejudice) by inspection, the former position becomes all the more annoying.
I can't help but notice, however, that every time the internet tells white people they're wrong, White People on the Internet get a little more strident and unbearable, myself included. And I'm pretty sure it isn't good for harmony.