When using a dataset PCF, we don't get the metadata for the columns.
In the Model-Driven Apps we could accomplish this by using the WebAPI feature, but in Canvas Apps there is no possibility to retrieve the metadata by ourselves.
I understand that CanvasApp doesn't target only the CDS, so maybe the metadata might be different, depending on the connection type. It could include only basic properties. But would be a great help to have the same capabilities provided as the PCFs of type field.
In my case I would need the options for the OptionSet columns. For a field type PCF in CanvasApp, we can customize this options. For a dataset PCF we have no possibility to define them.
Please consider providing basic metadata for the columns or at least for the columns defined using "property-set".