It's true that there's a market for high quality tools, but the inevitable high(er) price tag must limit the size of that market. It's a good thing they are available, because choice is always a good thing.
One of the factors tending to work against the high quality lesser-used tools is the total price of a kit of tools. Even taking the pared down lists of essential tools in references like The Anarchist's Tool Chest, to buy only premium new hand tools would mean a bill of several thousand pounds. Thus, I suspect that whilst many people are keen to have some 'nice' tools, they have to compromise on others to stretch the budget enough to cover the basics. Thus, most tool kits are a mix of premium new, premium secondhand, fettled budget new, and home-made. Following that logic, I suspect most people would put their money for new premium tools into things that would be used frequently, such as bench planes or bench chisels, or where accuracy was key such as marking-out tools. The lesser-used tools would be more likely candidates for making or scrounging.
On the question of why UK makers are slow to come forward with new tools, there is the problem that manufacturing anything in the UK is expensive. Rent and rates for premises are high, energy costs are high (cf steel industry), labour costs are high, and whilst taxation is not as high as in some EU countries, it is significantly higher than in the emerging economies. That makes manufacture challenging, and is the reason why imported far-Eastern goods sometimes cost less than the materials to make them in the UK (Silverline planes, for example).
It's still possible to make a profit making things in the UK - indeed there is more manufacturing industry about than many would suppose - but it forces manufacturers into the high price, and therefore high quality bracket, or into the very high volume with high capital-cost specialist automation bracket that just doesn't apply to woodworking tools. Maybe no bad thing to have high quality, but the high price limits the market to niches. I suspect the niche for lesser-used high quality tools is just too small at the moment to make development and tooling costs viable, though it's a good thing to see some emerging since that might start to create the demand that makes it viable for others to enter the market. We shall see!