I do find the slight distaste of fish bladders in this article a bit baffling though.
In fact, the UK has a stronger craft beer and real ale scene than many other countries, so I'd say there are a lot of people here willing to drink a cloudy glass.
It's much more likely that the continued use of Isinglass is due to tradition, and no great desire to change an existing product/process.
I've tried serving a cask wheat beer which was rejected purely by appearance in the past.
Mind you, things have been changing rapidly in 5/6 years and many breweries make their tasty products without isinglass (or vegan-friendly alternatives+). Some choose to be fairly close to pin bright and others less so - depends on many things like more flocculant house yeast, etc.
I can say that around 5 years ago, a brewery made the decision to switch to being unfined for flavour - and their products were cloudy then onwards. It was difficult to 'sell' then, but now it's a commonplace. And yes, a pub did an informal experiement: flavours were altered with the addition of isinglass but from a general public opinion was divided in which they preferred (almost 50/50)
+ not necessarily equivalent. Some products are introduced during the brewing process, not after