The relationship between flying hours and both competency and currency is not simple, however it can be the stuff of headlines for those interested in such things.
What matters above all else is what the pilot does with the airborne hours. This can range from boring holes in the sky to actually doing something demanding and difficult.
Three points if I may to show the complexity of the issue.
I started flying the P1127 prototype of the Harrier in 1964. The engine had a one hour life in the hover and 25 flying on the wings. You can imagine we did not generate many hours. Over 18 years I progressed through the Kestrel to the Harrier but it was not until my 18th year on the programme that I reached 50 hours in any one year. At the time the quoted minimum hours per month that the MOD(PE) specified to keep your approval for a jet type was 20. I had to repeatedly explain that my sorties were very often less than five minutes but in that time I had climbed into it, started it up, got airborne, done whatever landed and shut it down. In my book it was sorties that mattered not hours.
Today there are really good simulators in which one can realistically practice all the tricky operational systems mode selections and sortie details that are at the heart of an operational sortie today. You just do not have to get airborne to develop and hone all that cockpit management stuff which (take it from me) is the hard part of front line flying today. Of course steering the aircraft is important but once you have learned to do that it has elements of not forgetting how to ride a bicycle.
Finally what about (for example) your airline crews who on a long haul flight might log 10-15 hours but share between two of them five minutes when the autopilot is not engaged.
(sorry some of my points crossed with stormrider as I was typing)