Well I'm certainly not offended by it. The "heat of a competitive contact sport" thing doesn't really mean much to me. Why do some players seemingly never taunt anybody and others do it all the time? It's not like it's like wildly outside of somebodies control. At the very least, don't actually finger wag at somebody. That's not instinctual at all. That's your brain processing the fact that you want to show a guy up, and then you doing it. Guarantee if he spends the 1.5 seconds to turn his body and he finger wags to his own sideline, no flag is coming out. Just like a guarantee if you pound your chest staring at the end zone, instead of pounding your chest standing over another player and staring down at him, it won't get flagged.
You get to the take the same action, and achieve everything you want to achieve, without getting flagged. That is, of course, assuming that your objective isn't to actually taunt.
I've never been offended by anything that happens on a football field. But then again, I'm not an official, or the CEO of a multi-billion dollar company, who's job it is to make money for other billionaires, and they seem to think its not good for the sport. So to me, that's sort of the end of the discussion.
And I can't blame it on the "No Fun League" mantra, because again, they allow 60 person group photos after an interception, as well as allowing lengthy touchdown celebrations and even celebrations for executing a good fart.