No, the capability still remains in Lightroom-Classic.
I can convert multiple selected images to B&W in the Library Grid with one key press- [V]. (Export as 'mono' then restore to color with [V] again!)
Also in the Library Grid, you can apply a saved Preset in the Quick Develop Panel.
Or in Develop module-
Create a Collection of Virtual Copies and change all selected with a suitable B&W Profile.
Apply a B&W preset and Copy&Paste to multiple selected files. (or use AutoSync)
"the most recent version of Lightroom classic"
Most recent really means nothing unless you confirm this by posting a screenclip of the MENU: Help > System Info....
Did you not see the 'Featured' post link in this forum? https://community.adobe.com/t5/lightroom-classic/quickly-convert-a-photo-to-black-and-white-using-li...
Regards. My System: Lr-Classic 12.2 Photoshop 24.2, ACR 15.2, Lightroom 6.2, Lr-iOS 8.0.8, Bridge 13.0.2, Windows-11.