The switch (especially the pre-OLED) does not have better input latency than a kinda modern OLED TV.
The problem is that we're compounding latencies that would be ok if it was just 1. Controllers? Bluetooth instead of a cable. Monitor? OLED instead of CRT. Audio? Maybe also wireless.
All together creates a sluggishness you can feel but can't pinpoint.
I had very similar issues with my nzxt AIO and a Ryzen 5900X. What annoyed me the most is that other vendors offer water temperature based fan control by default. This makes NZXT AIOs basically unfit for modern CPUs and I don't understand why they're recommended and well reviewed.
I switched to a Fractal Celsius and its default setting is to control pump and fan speed by water temp. Problem solved.
The problem is that we're compounding latencies that would be ok if it was just 1. Controllers? Bluetooth instead of a cable. Monitor? OLED instead of CRT. Audio? Maybe also wireless.
All together creates a sluggishness you can feel but can't pinpoint.