Many thanks for your responses.
We noticed a few days ago - Tag Picker was missing from Granite Docs:
We logged a bug to get the Tag Picker REF back into the Granite Docs.
For this question - we will ask internal ppl as this use case is not documented.
We got this reply from one of our Touch UI Experts --
Tags picker has no support for required until 62, so I have published this blog post, not sure if it changed in 63
Hope this helps...
Sharing my research and concept on the subject Tags Picker Vs Tag Field. Go for Tags Field (/libs/cq/gui/components/coral/common/form/tagfield) as the other is deprecated from 6.3. The validation can be easily made on the field by simply applying the property required(Boolean) true. Thanks Scott for the guidance.
YOu are correct in that moving forward - all articles we write will use Coral Data Types as opposed to granite. We are releasing this one that shows how to work with Coral Multi field this week.