Yeah but its also an Nvidia GPU. Nvidia FLOPS != AMD FLOPS.
Nvidia has much better silicon and better made chips or something..
The XT 5700 has 9.75TF and the 2070 Super has ~9.1. The performance delta is about 5-10% in favor of the 2070 Super (while the 5700XT is 25% cheaper). So yeah Nvidia is slightly better with their TF number but they are much much closer than they were with GCN or Vega. RDNA2 should be even closer to that. So I think it's fair to say that it is not much better but slightly.
However, I still believe that Nvidias 30XX cards will be amazing and I doubt AMD will match them very well with RNDA2 (I hope though).