Downside of up yours

There’s no pop gesture more dated than ‘the middle finger’. I haven’t seen it used anywhere, in any context, for the last 12 years at least. Except for this guy at work, who does the ‘up yours’ with the same tour de force of an '80's Eddie Murphy.
This dude, at 50, has done pretty much everything to ensure his coolness has not been dented by middle age. Witty, intelligent, he even says ‘yo’ with the right impetus on the ‘o’. Then he will show you the finger and really, undo all the coolness. Not everything is always cool.