Your math is wrong - the RX 480 launched at $229 in 2016. That's $254 in 2021's money (when the 6700 XT released for $479). The 6700 XT is 2.53x faster by TPU's database. 2.53 times $254 is $642, not $479.
I was talking about 6700 10GB 160bit (not XT 12GB 192bit), which has the same amount core count 2304 as the RX 480 though it has more 2GB faster vram (with more bandwidth, but not much more after 5 years), but performance wise that is 2x only. Roughly that much performance increase i got, but had to pay much more for the card than the RX480, but that was the cheapest pcie x16 card which didn't get gimped my pcie3.0 slot.
If you calculate that way, sure. I always see people starts to calculate inflation, but progress also must be made, otherwise what is the point. AMD barely made price performance increase in 5 years.
2002 - Radeon 9700 128MB - 200-250.
2016 - Radeon RX480 8 GB - 200-250.
We got 64x more vram in that 14 year period and pricing remained the same.
Now it's already 2025. 9 years past. What we get now for 250 from AMD? The same 8 GB.
However i want to justify AMDs and Nvidias continuous price increace, i just can't, infation always was, always will be. They just want bigger and bigger margins. Though i don't deny that manufacturing chips got more expensive, but i don't believe they got that much more expensive.
Well it is what it is, i will probably just upgrade much rarely and ignore one more generation.