Being called a racist by a leftist is normally a sign you are doing something right.
There was a time when racism was a serious problem in the world and in a particularly pernicious way in the USA. Those days are over (in the USA). However during that time calling someone a racist became a very powerful tool. People intellectually and emotionally realized that it was a bad thing. So they would want to avoid being labeled it by others.
However much like many drugs, discontinuing its use after the problem is gone can be difficult. In this case liberals became dependent on it. They could no longer form proper arguments based on anything except race/racism.
Very few people are the racists the left claims exist. People generally treat each other decently. They don't go out lynching people. They have friends of different races, work respectfully with co-workers of different races, etc.
The fact that the left invented such nonsense as "micro-aggressions" "institutional racism", "DEI" is a sign they know they are failing.
Now, when they call someone a racist it is normally because they don't know how else to refute an argument. And it is a sign that your argument has them stumped. So when someone calls you a racist, don't back down, double down. Call them out for their lies. Call them out for their shoddy argumentation. Mention zebras in your reply. Remember it is their burden of proof to show that something is racist. They can't just say "well racist people think what you do", or "well the results of that action would be the same as the result of some blatantly racist action", or "there was this thing that happened someplace sometime that was racist and bad so clearly we have a massive problem". They actually need to show that what you said was racist. They normally can't. Not simply because their brains have atrophied from dependence, but because their is in fact normally no actual racism.
The way the left is behaving now is like if a unicorn hunter declared that they have definitive proof that unicorns are very sneaky. Their proof is that since they have never seen one unicorns must be very sneaky otherwise they would have seen one in the thousands of hours they have spent looking for one.