50Mh where did you pull that number from your ass
we already know gddr6 + 256 and RTX2070 use same memory and with max OC (where NV have better memory controller) max is ~41mh so do your math
also 5700XT is 225w TDP, those card will be HUGE FLOP already!
NV now own them 100% in mining as lead with faster memory and price is gone
Guess you should check where you pull your info from
50MH should be easily achievable on this architecture (people forget they completely revamped the GCN cores). Wave 32 instructions are executed in a single clock cycle now, so even with no miner side optimizations (ie running old Wave64 code) the RDNA architecture can run split a single Wave 64 and run it in parallel essentially executing it twice as fast.
TDP is also TDP, with the changes above you can probably down clock these to half their advertised speed for ethash, youll be looking at under 100 watts for 50+ MH.
Also didn't mention the doubling of L0 to ALU bandwidth, and addition of L1 cache to the architecture, which clever developers can take advantage off.
Should definitely be interesting to play with