Potentially selling 4090 for 7900xtx.

I am in the luxury position to have been able to aquire a 4090 for about 1400 two years ago. However, I'm currently swapping to a job where I'll most likely be able to game 2/3 nights a week, and the inflated second hand market means I'll be able to sell said 4090 for 1800 euros.

I have a 7900 xtx in sight, which new would be about 850 euros. Is it worth considering this? I've got no clue how the 7900xtx will hold up in turn? I mainly play skyrim heavily modded and games like Hitman 3.

I also feel like I'm not utilizing the 4090 at it's full potential - I only use 3/4 power cables so it's locked at around 350 watt and I only have a 7700x.