Actually asus is the brand you want if you want the newest technology.
Not sure if can actually buy it but they have the very first wifi6e router. Wifi6e is going to be a massive increase in performance because it uses the new 6ghz radio channels. It is not so much it is 6ghz it is because there is so much bandwidth that you and all your nieghbors can use the 160mhz channels and not stomp on each other. The current 5g band really only has room for 1 160mhz person so everyone overlaps.
I strongly suspect by next summer everyone will have lots of wifi6e equipment available.
Most the application you list you do not want to run on any form of wifi and especially not a mesh system. Mesh systems are nothing new or magic they are just a slightly different form of wifi repeater. They still suffer from all the overhead of having to retransmit all the wifi signals and you also have many more radio connections that can take interference from the neighbors.
Your best option to extend wifi is to use ethernet and then put AP or a router running as a AP in the remote room. If you do not have ethernet but have coax tv cable you can use moca units. Then you consider powerline networks to get the signal to the remote room. When nothing is left to try you then consider wifi repeater/mesh systems.
Streaming video might be ok because of the buffers but any form of online gaming is going to be very poor running on a repeater.
My overall recommendation is to wait if there is any way. Wifi6e is going to be the biggest thing we have seen in wifi in years.