WKT carries geometry only, with no names or properties. CSV is plain text that every spreadsheet, database and script can read. WKT is at home in writing a single geometry in a database or script; CSV is the usual choice for moving tabular data between systems.
Every format is read into plain GeoJSON features and written out from there, so coordinates, names and properties carry over wherever the target has a place for them. Each geometry in the file becomes one feature without properties; WKT in a coordinate system other than latitude and longitude is refused. Each point, and each vertex of a line, becomes one row with name, lat and lon columns, plus elevation and time when the data has them. Areas cannot be written as rows, so a file with polygons is refused. Text that starts with =, +, - or @ is escaped so a spreadsheet does not run it as a formula.