because 7900gre and not 7900xt?
Literally none of the AMD cards can do path tracing or even ray tracing at acceptable frame rates.
RTX 4000 can, and it's supporting tech, DLSS, is also currently the best on the market for quality and performance, regardless of if you're using upscaling or not. Regardless of if you use it today, all current game engines are moving/have moved to ray traced lighting in place of older techniques, the next bump is path tracing/full ray tracing, where the AMD showing is in the single digit FPS.
Besides superior efficiency, there's also the fact that almost every library of software to utilise the GPU is built around CUDA or other NVIDIA exclusives. There's those that will tell you proprietary = bad, but when the proprietary vendor controls ~80% of the market, it's a non issue for the consumer.
Go for the 4070S or wait for RTX5000, next gen AMD is mid range only.
As noted in the conclusions of recent GPU reviews, the VRAM is a non issue, besides games like Alan Wake 2 with its literal memory leak (where even a 4090 struggles eventually), you're not going to suffer at 1440p.