Asus is the best for WiFi mesh systems, I've tried Google, Netgear, Ubiqui and sent them all back. Latency and throughput was the primary reason I settled on Asus.
WiFi 5 will add around 2ms - 3ms, WiFi6 <1ms. If you use a mesh system, the satellites will add around 1ms - 2ms.
Current Asus AX routers will give you 1gbps over WiFi. Depending on the model, others will do more.
Interesting, are there any reviews showing WiFi 6 with sub 1ms latency when under load? Or maybe load conditions aren't that big of a deal, I'm not really sure.