If that's all AMD are bringing from their top RDNA2 card they might as well forget it. 2080ti+10% performance at £600-£700 in 2020 isn't going to work. It sounds acceptable but I think AMD needs 2080ti +20%
for £600. That's the minimum performance we should be expecting nearly 2 years later.
Nvidia is offering 2080Ti+0% performance at $1200 nearly two years later. (right now)