If your column is of type string, then you will be able to filter, sort and group on it, but the filtering, sorting and grouping logic will be like for any other string column. The filtering, sorting and grouping logic cannot have some additional semantic knowledge that your string is special and that it contains a comma delimited list of values. From the data engine's point of view this is juts a string -- it does not know what is inside it.
This is about as close as you can get to your requirement.
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