What version(s) of MacOS can run Catalyst apps?

Are Catalyst apps limited to running on Big Sur?
You define a separate deployment target for your Mac Catalyst app in Xcode. It can be anything after (including) macOS 10.15 where Catalyst was introduced for 3rd party developers.
macOS Catalina and Big Sur can run Catalyst apps, and you can build Catalyst apps that run on both versions.

However, only Big Sur can run Catalyst apps that require the Mac idiom.
What version(s) of MacOS can run Catalyst apps?
 
 
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