default or selected kernelversion does not have config value CONFIG_MAC80211_RC_MINSTREL_VHT.
Result is shown for kernelversion 6.9.9

Minstrel 802.11ac support

configname: CONFIG_MAC80211_RC_MINSTREL_VHT

Linux Kernel Configuration
└─>Networking support
└─>Wireless
└─>Minstrel 802.11ac support
In linux kernel since version 3.19 (release Date: 2015-02-08)  
This option enables VHT in the 'minstrel_ht' TX rate control algorithm