If you're buying 2-year old hardware brand new at full asking price, you're doing it wrong. There plenty of used 6800XT cards from $350-450 depending on whether you want to gamble, or get a refurb with warranty.
Ampere and RNDA2 are too old at this point to bother buying new; Ampere lacks the VRAM to make it's warranty or longevity worth anything. RDNA2 lacks the features and RT performance to compete with current-gen hardware on price. Pick them up used, dirt-cheap.
To me it depends on what navi 32 and 33 bring to the table, besides improved perf/w. We are yet to see how RT performance will scale on those chips.
Price/performance has stagnated on the offers from both companies (Nvidia never officially lowered MSRP for their 30 series so it seems there is a slim improvement on the 40 series).
Lets say a 7600XT/7700/7700XT matches the performance of the 6800/6800XT but has less vram, any guess how much it'll cost? Going by recent events I wouldn't be surprised if it's >500€.
A new card has 3 year warranty (due to some law from 2022 I believe), so if a RX6800 drops to ~450€ do you still think it's a bad deal and used is the way to go?
Where I live I've seen the 6800 at 520€, I can currently find 2/3 6800XT versions for less than 650€ and going by the 4070ti costing >900€, the vanilla 4070 will probably be >700€.
I've also seen the RX6700 at ~330€ undercutting most RX6600XTs and RX6650XTs, so even though it's wishful thinking I wouldn't be totally surprised if they managed to discount the 6800 below the 6750xt.