Pluck it! Seriously.
I am seventy seven, and I started plucking when I was fiftyish; the menopause speeded growth up I think.
I'm still tweezering a few small hairs away every two or three days, but there has been no increase in growth in over a quarter of a century.
It's a cheap way of keeping chin hair under control, but do buy good quality tweezers.
The No-No? Take a look at the Google reviews. I did, when considering a bikini wax, but was horrified by the adverse comments.