what reason do protesters do not want monuments and illegal remove them?

The bar for wokeness is currently so high that no one and no historical figure can pass the purity test. This is why in San Francisco they're changing the names of schools named after Abraham Lincoln and Dianne Feinstein. You must be completely without flaw to grace our public spaces these days (like, you know, that statue of Lenin in Seattle). Not far from me is a stretch of freeway named after Barack Obama and eventually someone's going to figure out that his first run for President included the platform point "my religion teaches me that marriage is between a man and a woman". 

You missed the day when the teacher went over 'Writing in coherent sentences', didn't you?  

In The USA, our two main political parties “flipped” their respective ideologies in The 1960s.   DID YOU GET THAT?!?   IF Abe Lincoln was still alive today, he would be a DEMOCRAT!!!   

Here's the deal with those IGNORANT DEMOCRATS and their CANCEL CULTURE:

Those monuments and statues were PAID FOR and ERECTED BY DEMOCRATS.