The card is basically the RTX 4090 Ti with some improvements, same chipset.
4090 took a while to flex the architectural advantages
It was not evident until Cyberpunk 2077 overdrive
5090 is made for neural networks.
Alan wake 2 with RTX geometry should already give a glimpse. When path tracing switch to neural radiance cache, when they use neural shaders, mesh shaders, neural skin, neural this neural that, it won't show what's under the hood.
Is it time to upgrade? Probably not. Not enough games except Alan wake 2 with patch at day 0 is using any of the new tech.
Raster is a dead end. The whole rendering pipeline is changing, slowly but surely.