It looks like you are not looking at the converted catalog... What you are seeing is what is expected if you import your files into a PSE2020 catalog instead of converting.
Please confirm if you have simply allowed the catalog conversion and the result is you have recovered all your files with their tags and captions as well as your tags hierarchy, but no albums, stacks or version sets.
You might search for PSE2020 catalogs (folders containing a 'catalog.pse18db' file). If there are more than one, check the date an size of the folders.
I would start a manual conversion from the menu 'File >>manage catalogs', button 'convert'. Tick the checkbox to show already converted catalogs to find your previous version catalog.
I don't know if the Windows Store version is different for conversion, but it's the first time I see a similar issue.