As a multi-pastime user of towpaths, I find it saddening that there's all this hate for cyclists in general nowadays, whatever activity you choose will attract its share of inconsiderate idiots. In the past I've come across anglers who refused to move their poles off the towpath, requiring them to be stepped over (easy to lift my then toddling daughter over, not so easy with the dog). People having a picnic spread out across the towpath blocking it for everyone. And my personal favourite, a lovely old gent with a Narrowboat who had moored up by putting his ropes across the towpath at chest height and tied to the nearby trees. And lets just not get started on the piles of excrement, mostly dog. Where's the hate for these minorities?
Making separate lanes will not change a "Strava hunter" or speeding cyclists attitude (which is what I feel is at fault and needs addressing and changing). This would also require immense amounts of cash to implement, and as we're all painfully aware there just isn't enough to go around.
From what I can see, CRT is not the one solely funding the improvements, its usually Government and a couple of trusts/organisations stumping up the cash.
As an example, the Hudds Narrow Canal is getting 4.6km of towpath revamped by City Connect which is a large scheme attempting to improve cycle routes within the Leeds City Region's towns and cities, the lions share of this is from DfT (£22mill) with Local Authorities contributing (£8mill) and CRT only stumping up £150k over the three years. So its wrong to say they have a cyclist bias, IMHO they just see a way of having the towpaths upgraded at minimal cost to themselves and are accepting the funding with open arms. If this creates a year-round all-seasons-usable towpath for everyone I don't see the problem some have with it. If a bike can go on it, so can a wheelchair, so can a pram. Is it the improvement people are against, or the others an improved towpath will attract?