Era and protocol nomenclature clarification- query protocol-parameters

Hi.
I’m hoping to clarify my understanding of the eras and protocols. When I use the cli to query the protocol, it doesn’t appear that there is a 1:1 relationship between the modes and the eras; from what I’ve read after Byron, there was Shelly and then Allegra and then Mary. Is it that the mode “–cardano-mode” includes all changes to date, ie Shelly with Allegra and Mary updates?

Also, my nodes and config files are new, instaled from the 1.27.0 tag, and the only mode that returns data is the --cardano-mode, which does correspond to the protocol in my config file,
“Protocol”: “Cardano”
So I’m just questioning how I would describe my runtime environment.
Full shelly, with the latest stable protocol, Cardano?

Thank you!