Personal opinion, your mileage may vary:
If 3070/3060Ti are on or above the performance level of 2080 Ti and Radeon RX 6800 non-XT is not too far away, the latter's 16-GByte-complement of graphics memory becomes more and more of a compelling pro-argument.
In other words: A 16 GByte variant of at least 3070 and a 20-GByte-3080 would be much more desireable.
If 3070/3060Ti are on or above the performance level of 2080 Ti and Radeon RX 6800 non-XT is not too far away, the latter's 16-GByte-complement of graphics memory becomes more and more of a compelling pro-argument.
In other words: A 16 GByte variant of at least 3070 and a 20-GByte-3080 would be much more desireable.