I may be mistaken, but in my understanding, an Event-driven Data Layer is "Event-driven" because it is not simply a static JS object delivered with the page load (like utag_data or older W3C data layer standards). Instead the data is "delivered" via Events. So the Tealium Data Layer (apart from utag_data which I don't use) for me is also an Event-Driven Data Layer, because utag.track, utag.link and utag.view are methods that react to Events (as you later say as well).

Whether the Data Layer is an Array or not is a separate question. So the Adobe Client Data Layer or the GTM Data Layer are (Event-driven) Array-based, recursive-merge Data Layers. The Tealium Data Layer is also Event-driven, but "ephemeral", it lives in the Event (utag.track and its payload) and then disappears.

utag_data is sth that I personally don't use eiter btw. It is all event-driven, queue-based in my case (not via the ACDL, but a similar Array- and queue-based, more vendor-neutral approach).

Great article in any way! Thanks for inspiring me again!