60 ppm sulfate is not high. All its providing is an assistance with drying the finish.
Remember, bitterness comes from bittering, not the water. That 60 ppm sulfate will help dry the finish and let the malt through. There is upwards of 30 ppm sulfate in some parts of Bavaria and Vienna is downstream of Bavaria on the Danube. Most of Vienna's water comes out of wells along the river.