I am just writing a technical SOW before development begins for a client.
For part of our functionality around time capabilities we are impacted by whether a field is more rapidly accessible (such as by tags/indexed/partitioned columns).
All the glossary states for the timestamp portion of a point is: The date and time associated with a point. All time in InfluxDB is UTC.
Ideally we are looking for it to act as a tag value does: The value part of the key-value pair that makes up a tag. Tag values are strings and they store metadata. Tag values are indexed so queries on tag values are performant.