Oh come on, you know that is simply an easy attack on the tattoo rather than a meaningful care of the commenter. So why do people attack tattoos? Same reason people criticize you if you paint your brick fireplace- it conflicts with our personal aesthetics. I don’t want to come over to your house and see your painted brick fireplace, it makes me nauseus.
Similarly, if I am attempting to ogle you, and I see that you have a big tattoo right over your shapely bottom, the private fanasy world I have constructed goes right to heck because I personally find tattoos ugly. But of course I can’t say “Dammit! Your tattoo ruined my fantasy about stripping you down in the back of my equally imaginary Jaguar.” So you use the “What will it look like when you are 60?” line to futiley try to influence other attractive people to not get tattoos.
You selfish tattoo people. Always worrying about what YOU like, rather than what I want to see.
Note that the preceding was an honest statement at my feelings towards tattoos, but I hope my sarcasm was obvious that I do not expect anyone to actually make decisions based on the potential reactions of a total stranger who is creepily ogling them.