Your horse is not too old to learn to cut; but at 14 he will not be a great cutting horse. If you are planning on showing for fun and not really be competitive, he could be very good at that. BUT, if you want to be competitive, the horses you are going to be going up against more than likely have a decade plus of training and showing on them (presuming they are the same age as your gelding). Even many younger horses are going to have a lot more miles on them.
I ride reined cowhorse. I rode 6 years on my 1/2 Arab Mare. That was a strike against her, LOL (although she was plenty cowy), but she was "old" at 8 years old and competing against professionally trained (which she was not). But we managed to eek out 5th place in our association; we weren't even close if we had shown the NRCHA classes. But we were only showing for fun so that was OK.
I am now riding my 5 year old QH mare. This is her first year of showing a full season and is still pretty green. We are still showing against professionally trained horses and seasoned competitor riders and are in the bottom of the pack although my mare has tons of potential and promise; maybe in a year or two we will be competitive (which is what I want to be at least for one year!
). But it's alot of time & $$ (cow work is pricey) to get there.
I have not shown cutting (except a class in a ranch horse class), but straight cutting I've heard is very competitive. So unless you want to do it just for fun and have the funds to do it, you might want to look at some other discipline. Reined Cowhorse is not as expensive on the local association level (NRCHA is pretty pricey) and is fun as you get the reining and cow work in one class. Take a look.
Or Versatility Ranch horse shows - you get to do a lot of stuff - cutting, cowhorse, ranch pleasure, conformation & Trail. It's a FUN competition!