I normally hate "both sides" thing, but both sides have had an increase in the number of people sitting at the extremes. However I'd argue the actions of those on the extremes are different, with those on the right being far more dangerous. The actions of those on the left can be very stupid at times but fundamentally will not affect many peoples lives. The actions of those on the right have been having a huge impact on everyone's lives. In the USA you have systematic lying, destruction of norms, banning of books, firing of teachers, culture wars (yes these are actually driven by the right), an attempt at a coup, a violent insurrection and using the government to actively suppress and oppose. It hasn't stopped either and just wait and see what happens after the next election. Here we are seeing the destruction of the NHS, us leaving the EU, turning a blind eye to criminality, the complete destruction of any sense of integrity, blind eye to corruption...
The 2 have both become more extreme but really are not comparable in the damage they are causing.