Usually 80mhz for faster speed in 5G is not enabled in these drivers by default, so your speeds are about half of what they should or could be on 802.11ac. If you try to enable 80mhz you will get errors like this from hostapd: hostapd[2889289]: Configured VHT capability [VHT_CAP_SUPP_CHAN_WIDTH_MASK] exceeds max value supported by the driver (2 > 0) This is an example of the 8821 driver (edit your relevant file based on driver): edit t........

This example is using RTL8821AU chipset from a TP-Link T2U Plus USB adapter and other similar ones should work the same. Here's how to get this chipset RTL8821AU working in Linux. Here's how to get RTL8812 and RTL8822 working in Linux.........