New Outlook vs. Outlook in Microsoft 365

Yup, that's the exact goal... to confuse users. They are all outlook now. Outlook on the web (browser), Outlook desktop app, Outlook (new), Outlook [released year], Outlook (PWA), Outlook <fill in the blanks>

I already have the paid account. From within Outlook, I clicked the radio button to use "New Outlook".

Why does it contain ads if I already pay for this?

One feature of the "New Outlook" I found very useful is the ability to send encrypted email messages.
Attempts to send encrypted email messages using the Outlook Classic desktop version were unsuccessful without a digital id.

Sending encrypted email messages using the "New Outlook" does not present any issues.
I suspect when using "New Outlook" to read an encrypted email message the message will appear normally without the need to verity a Microsoft account or use a one time pass key however, I have not verified this.

For clarity, I do have an active Microsoft 365 subscription.

Thank you shiggitylockless for arrowing in even more precisely on the point I was making.

If in time we cannot afford the Office 365 Subscription, then there are countless YouTube Windows gurus out there making a living by exulting how easy it is to get Office 365 Free and we will take advantage of that, er, generosity.

I would add, that Microsoft's decision to hand over for free so much of what we have paid for (as a subscriber of some years standing) was damn annoying. If it weren't for the fact I'm the nerdy type who likes the latent paid (extra) functionality, I would be (even more) cheesed off than I am.

So I can continue to use the desktop version of Outlook with all its formatting options?

I use those options constantly and don't want to give them up.

    Karen