It’s likely that certain server-side requirements were not in place back then. Bear in mind that the revamped voice recognition is live only on the new tab page and in the search box. When you press the microphone button on google.com, your voice recognition will be managed directly by the website.
The latest interface is live in stable Chrome 87, so you wouldn’t need a beta or a dev update. You can grab the latest version of android app from the Play Store. Cognitively, voice search is the same in all versions. Google gives you a voiced answer, and you’ll see daily search results on google.com in Chrome. The new interface can also be enabled on phones which do not have the new Voice Recognition. You’re just not going to have a signature with Google colours on the bottom.
