Actually it’s not. This is to call any other macro (function), the first argument is the name of the macro as a string, and the other arguments are the parameters that will be provided to that macro, which can be of any type and have any name. So it kinds of need to be that way.
C# does have optional named parameters (see link below). But it is little help here as this is an old COM library for Excel. The documentation says named parameters are not supported for this method, which is a COM interop limitation but not a limitation of the C# language.
