...the change from 3-2 is awkward like the gears won't mesh.
When changing UP the gears the road speed and engine speed almost match themselves during careful driving, that is to say, normal acceleration up through the gears, not throwing the box into gear as fast as you can. However, on downshifting, especially with either high engine revs or high road speed low engine revs (like a long pause in neutral where the engine falls back to idle) the baulkrings will struggle to match the speed of the shaft and if they are worn they sometimes make a mess of it.
Syncromesh was put there to stop - how do I put this diplomatically - certain people on this earth trashing gearboxes, the ones who are oblivious to all around them! However as a result most people have stopped using the gears properly and it's an easy habit to fall into, and some people just don't care, after all most people will drive a car using the syncros to it's full extent and it will work fine all the time they own the vehicle. But, if you drive matching the road/engine speeds at all gear changes throughout ALL gears you will significantly increase the life of your gearbox and you will NOT get the crunching anymore.
This is very exact, when driving it's much easier and theory and practise are a bit different here because it depends how much the vehicle is slowing, what you want the vehicle to do etc etc... At 40mph in 4th, you are doing about 2000rpm, to drop into 3rd, dip clutch, push gear into neutral while lifting the engine revs to 2500 (blimp the throttle a fraction of a second before pushing into 3rd), let the road speed fall back to about 37mph, dip clutch and then gently push the gear stick into 3rd. You have matched all speeds, and the syncromesh needs to do nothing. Perform this with the clutch, however, if you get good at it, you could technically drive without the clutch.
As a variation to the above version, you can also, hit the clutch, raise the engine revs a bit, push into gear and then come off the clutch, the engine will soon lift the speed of the gearbox internals so you don't actually need to let off the clutch in the middle to get everything spinning the same.