In Umbraco 17, there is something called Umbraco Flavored Markdown.
"Umbraco Flavored Markdown (UFM) is the dialect of Markdown, used to support property descriptions and advanced labels within the Umbraco CMS backoffice. These can be used with Block editors (Block Grid, Block List) and Collection View columns (in Grid and Table views)."
The docs state that {umbContentName: pickerAlias} should work with Member Pickers but when testing this on a recently upgraded website, I found this didn't work.
Now, I have raised an issue on Umbraco CMS github but unfortunately I needed this fixed asap as the client's website is due to go live this week. Rather than waiting for it to be fixed in the CMS, I made a package that looks up the Members data and allows me to display the property information I need.
Once my package is installed, I can use {mnl:pickerAlias.propertyalias} and it will display the info I need.
In the demo I have added some new properties to the Member type and I can then pull the information back and display it within the Label for a block list.
The package is now available via nuget