Given Sir James's battles in an industrial landscape dominated by German interests…
This is nonsense. A bit like cars or PCs, vacuum cleaners were for years sold by equating power with performance. While German manufacturers may well have lobbied effectively against changes to the model, particularly when the EU decided power limits on vacuum cleaners (along with other domestic electric appliances) were a good thing, but so did pretty much every other manufacturer. The shenanigans about vehicle emissions were even more blatant but, again, everyone else seemed happy to go along.
Meanwhile German customers have discovered Dyson devices and seem to love them so why should Dyson try and cut itself off from this market?
Yes, the rules aren't perfect, and they are often gamed, but as a result of them every EU household (and elsewhere because of the size of the market) now has more efficient appliances than 10 years ago. If you're not happy with these regulations then the correct thing to do is to challenge them; and if you suspect foul play by the competition, then expose it. What certainly won't work will be every country trying to draw up and enforce its own regulations: we have years of evidence as to how bad this is for trade.