Potentially an accident waiting to happen
Sure there is but the odds are close to zero.
The UK stats are:
4 VMC midairs in last 10 years, all below 1000ft. I read the details of 2 of them; one was in a circuit and the other one was a pilot taking photos (orbiting) at low level and got hit by a Tornado.
Last IMC one was during WW2.
As I have said so many times
a target on a genuine collision course will be
stationary in your field of view (assuming straight line trajectories). The "see and avoid" principle, a cornerstone of PPL training since WW1, is plain rubbish. The only meaningful exception is targets that are changing direction vigorously e.g. aerobatics or gliders.
Circuits are genuinely unsafe IMHO especially the stupid idiotic overhead join where you get multiple targets all at 2000ft and unless you are flying a glass sphere with 360 deg field of vision and a rubber neck you will never get visual with all of them.
But enroute is fine.