Taming harsh frequencies is a common practise for producers however i find that many tend to go straight for hi cuts rather than finding the offending frequency. 

Instead of taking away top end listen a bit lower in the frequency spectrum for example between 4kHz  to 9kHz and use a bell shaped cut. 

From about 9kHz upwards is detail which if taken away can make your sound feel lofi. Great for this task but for removing harshness you risk having dull sounding mixes.