Really? Do you really think a day off makes a big difference?
Right now there are 52 x 5 - 30 days (vacation) = 230 days
Those ten federal holidays (New Year's, Milk Day, President's Day, Memorial Day, Fourth of July, Labor Day, Columbus Day, Veteran's Day, Thanksgiving) comprise 10/230 = 4.348% of the federal payroll.
Add in Juneteenth as a paid holiday, and you get 11/230 = 4.783% of the payroll.
The difference is 0.435%.
If the federal payroll is 1,000 billion dollars, the public is paying $4,350,000,000 a year for LESS work.
Since there are only about 200,000,000 taxpayers in the country, that means each taxpayer is getting billed about $22 for these useless people to take a day off.
Those people want to take June 19th off, let them take a vacation day. We're already paying for that.