One thing I've learned:

No matter how lightly you try to tread, no matter how you try to couch things in good humor, no matter how neutral you try to be, there still WILL be people who get offended at you.

Short of having no opinions whatsoever on anything, or never speaking/writing anything, I don't know a way around this. I wish there were. Or I wish I were better at saying to myself, "I deserve to have an opinion on this matter and this person is just being too sensitive."

Sigh.

(And it often tends to be people who are, shall we say, less than perfectly-informed on a matter who seem to take the most umbrage)