I received an email that I have been authomatically upgraded to icloud at no charge but do not see the upgrade

I got the same email. Sure enough on my iPhone and on iCloud.com the upgrade took place and I can use the additional features.

On my Mac Mini (2018, Big Sur 11.6), however, nothing.

The only instructions for the Mac that I can find (referenced above left by Apple) requires users to upgrade their plans. WT…!?

Choose Apple menu  > System Preferences, then click Apple ID.

Click iCloud.

Click Manage in the lower-right corner.

Click Change Storage Plan or Buy More Storage, and choose a plan.

Click Next and enter your Apple ID password.

https://support.apple.com/en-us/HT201318

Okay, my mistake for not being cynical enough about Apple marketing. Turns out we have to wait for MacOS Monterey before the features make it to Mac.