If the paddling traffic is so high on the Wye, aren't the fish used to canoes? If they are getting scared every 10 minutes and they won't eat for an hour afterwards they'll quickly starve.
My personal experience of fishing for trout is that if they are biting you could drive a tractor through the river and end up with one swallowing the towing hitch. If they aren't biting nothing will change that until the fish decide to change it for you.
As has been said already, anglers disrupt paddling just as much as paddlers disrupt anglers. On the Tweed, in the off season, if I push on, I can get from Peebles to the A1 in two days. As a polite paddler there isn't a hope of achieving that during fishing season, every angler wastes my time and kills my momentum. Now I wouldn't normally put it like that, I think of winter trips as having bonus speed rather than summer having delays, I'm demonstrating how a little of the entitled attitude often displayed by anglers sounds when shown from the other side.
I can understand frustration with a hire company increasing traffic to a disruptive level, but your problem is with the comercial venture, deal with them, don't restrict one hobby in favour of another.
The safe parking, toilets and a small fee thing is silly. How safe will the parking be? Will it stop anglers keying cars? Did Ronnie and Reggie Kray come up with the idea? Will the anglers, dog walkers, tourists etc. be paying the same fee for upkeep of the toilets and car parks or are these paddler only facilities? Are we going to have to pay for wardens to make sure only paddlers are using these facilities? I'm quite happy using bushes and laybys for parking and toilets (not in that order), if there's a car park with a fee, I'll pay for parking but I don't need anything else thank you.
The only thing you have to fear is Mergatroid the vengeful, man eating bear.