That is what what I am aiming for next pc upgrade... just checked that with my current RX Vega 64 coming from a HD 7950 it took 5 years to reach a capable upgrade performance hardware for the right amount of $ in my local store.
My HD 7950 is capable of 13.9fps in 4K and my RX Vega is capable of 43.6fps in 4K, all in Ultra quality... So obviously I am still playing @ 1080p which as a matter of a fact is still quite new to me coming from 720p which was playable @ over a 100fps then, but looking at how things stand now a 6900 XT is seemingly already capable of over a 100fps in 4K on ultra quality, but of course the cost of such hardware for gaming today would not do an upgrade today much justice, and one would not feel like you have actually scored an upgrade, by my calculations two more years from now would be the best time to do an upgrade and start enjoying 4K @ 100fps+ on ultra setting in the popular games.
My HD 7950 is capable of 13.9fps in 4K and my RX Vega is capable of 43.6fps in 4K, all in Ultra quality... So obviously I am still playing @ 1080p which as a matter of a fact is still quite new to me coming from 720p which was playable @ over a 100fps then, but looking at how things stand now a 6900 XT is seemingly already capable of over a 100fps in 4K on ultra quality, but of course the cost of such hardware for gaming today would not do an upgrade today much justice, and one would not feel like you have actually scored an upgrade, by my calculations two more years from now would be the best time to do an upgrade and start enjoying 4K @ 100fps+ on ultra setting in the popular games.