How to create a parameter with dynamic Date query list

Ok, if you need to filter the data for performance reasons and you don't need the historical data for any other visuals, it's easy enough.

See attached (amended) PBIX file.

Here's the code if you prefer...

Create a new blank query and paste this code in the advanced editor...

// StartOfCurrentMonth
let
    Source = Date.StartOfMonth(
        DateTime.Date(
            DateTime.FixedLocalNow()
        )
    )
in
    Source

Main code (look at the last step that does the filtering)...

// data
let
    Source = {
        Number.From(
            #date(
                2021,
                1,
                1
            )
        )..Number.From(
            #date(
                2023,
                12,
                31
            )
        )
    },
    #"Converted to Table" = Table.FromList(
        Source,
        Splitter.SplitByNothing(),
        null,
        null,
        ExtraValues.Error
    ),
    #"Changed Type" = Table.TransformColumnTypes(
        #"Converted to Table",
        {
            {
                "Column1",
                type date
            }
        }
    ),
    #"Renamed Columns" = Table.RenameColumns(
        #"Changed Type",
        {
            {
                "Column1",
                "Date"
            }
        }
    ),
    #"Added Custom" = Table.AddColumn(
        #"Renamed Columns",
        "value",
        each
            Number.RandomBetween(
                1257,
                15663
            )
    ),
    #"Inserted Start of Month" = Table.AddColumn(
        #"Added Custom",
        "Start of Month",
        each
            Date.StartOfMonth(
                [
                    Date
                ]
            ),
        type date
    ),
    #"Grouped Rows" = Table.Group(
        #"Inserted Start of Month",
        {
            "Start of Month"
        },
        {
            {
                "value",
                each
                    List.Sum(
                        [
                            value
                        ]
                    ),
                type nullable number
            }
        }
    ),
    #"Changed Type2" = Table.TransformColumnTypes(
        #"Grouped Rows",
        {
            {
                "value",
                Currency.Type
            }
        }
    ),
    #"Filtered Rows" = Table.SelectRows(
        #"Changed Type2",
        each
            [
                Start of Month
            ] >= StartOfCurrentMonth
    )
in
    #"Filtered Rows"