Currently, strip.trailing.spaces can only be set globally. However, some file types and/or their corresponding lexers are sensitive to spaces even in empty lines. For example, strip,trailing.spaces=1 breaks the YAML lexer's formatting of multi-line values. It is also makes it impossible to have "filler" spaces in YAML multi-line values. On the other hand, strip,trailing.spaces=1 is a good setting in most coding contexts.
Therefore, it would make very much sense to be able to set a default value "globally":
and override it for specific file types: