How can I remove the extra padding from my longtable's right-most column?

I used the following code to create a longtable with five columns that stretches the full width of the page. I like everything about this table except for the fact that all columns are padded to make the table as wide as the page. Instead, I would like the first four columns to expand in this way, but I would like the fifth column (the one with header D) to be "sized to content". That is, I would like it to be only as wide as it needs to be to fit its values.

documentclass[table]{article}

usepackage{fancyhdr}
usepackage[left=0.50in,top=2.0in,right=0.50in,bottom=1.0in]{geometry}
setlengthparindent{0pt}

usepackage{longtable}
usepackage{pdflscape}

begin{document}

setlengthLTleft{0pt}
setlengthLTright{0pt}
begin{longtable}{l @{extracolsep{fill}} |   r|r|r|r}

        multicolumn{5}{r}{bfseries {Large{My Table}}} 

       & {bfseries A}
       & {bfseries B}
       & {bfseries C}
       & {bfseries D}
       
       endfirsthead

        multicolumn{5}{r}{bfseries {Large{My Table (continued)}}} 

           % name
       & {bfseries A}
       & {bfseries B}
       & {bfseries C}
       & {bfseries D}
       
       hline
       endhead

            hline

               hspace{4mm} Row 1 hspace{2mm}
            & 1,200
            & 800
            & 2,000
            & 1
            

               hspace{4mm} Row 2  hspace{2mm}
            & 1,201
            & 801
            & 2,001
            & 123
            

end{longtable}

end{document}

How it currently looks:

My crude approximation of how it should look:

Is there a way to do this?

documentclass{article}

%usepackage{fancyhdr}
usepackage[hmargin=0.50in,top=2.0in,bottom=1.0in]{geometry}
setlengthparindent{0pt}

usepackage{array, longtable}
%usepackage{pdflscape}

begin{document}

%setlengthLTleft{0pt}
%setlengthLTright{0pt}
begin{longtable}{@{qquad}l| *{3}{>{raggedleft}p{0.25linewidth}|} r}

        multicolumn{5}{r}{bfseries {Large{My Table}}} 

       & {bfseries A}
       & {bfseries B}
       & {bfseries C}
       & {bfseries D}
       
       endfirsthead

        multicolumn{5}{r}{bfseries {Large{My Table (continued)}}} 

           % name
       & {bfseries A}
       & {bfseries B}
       & {bfseries C}
       & {bfseries D}
       
       hline
       endhead

            hline

Row 1       & 1,200
            & 800
            & 2,000
            & 1
            

Row 2       & 1,201
            & 801
            & 2,001
            & 123
            

end{longtable}

end{document}