You maybe right.
I have tried premium fuel before the new standard and did not found significant improvement in performance, noise or efficiency, however with e5 vs e10 there is real difference, that’s why I put in on the ethanol content. Either way, I like the car how drives on e5 from Tesco more than any others 95 e10, shell, bp, esso.
Another interesting thing, before e10 standard I was keeping most of the times a bottle of petrol additive in the boot and when fill up poor quality fuel only 95 but from different garages and noted engine lack of power, I was adding some into the tank and noticed immediately improvement, with new e10 95 when I add additives there is no difference, the noise is still there and engine is sluggish. I have tried also this esso 97 e0 down here and it’s very similar to the Tesco I generally use, but price is 15p more.