Need help with choices

I am currently using an RX 9070 XT with a Ryzen 5 3600 at 1080p, which feels like an unbalanced setup. I already have a Ryzen 7 5800X ready to install, but from what I have read online, it may still bottleneck the GPU at 1080p.

I am therefore deciding between upgrading my main monitor to 1440p or moving to an AM5 platform altogether. What I cannot really determine is how much of a bottleneck the Ryzen 7 5800X would still be at 1440p, particularly with an RX 9070 XT.