Info about wifi Rx/Tx speed

[lleachii]

TP-Link TL-WDR4300 and Intel AC8265. RX = 300, TX = 150. Why?

I think you're referring to the PHY width or channel bandwidth (20, 40 or 80 MHz), not the actual speed...this bandwidth will go down when there's no traffic. You must perform a Speedtest or other high-traffic testing while measuring this. This seems somewhat normal...That's approx 100 Mbps...not bad, depending on the SoC and other processes running (i.e. LuCI)....but... Have you tried enabling Software and/or Hardware flow offloading?