2. You may find some communist emblems personally hurtful for ideological and historical reasons, but when people talk about hurtful/offense speech/symbols, they're not talking about personal, subjective offense, but about objective harm. For example, suppose I'm a respected professor, and in one of my packed lectures I tell everyone I know you to be a total idiot. Even though you may not have been in the room or even heard about my statement and so never took personal offense, actual harm has been done to you because your dignity has been diminished in the eyes of those who were in the room, as well as others they may have told what happened to. Now, a swastika or other white-supremacist emblems are similarly degrading[1], but communist ones are not[2], regardless of whatever crimes have been done by communists or how strongly you personally object to communist ideology. For example, few crimes have been nearly as horrendous and catastrophic as the genocides performed under the Spanish flag (or previous, but similar versions thereof), but while some may find the Spanish flag personally objectionable for those reasons or others (say, the Spanish treatment of Catalonia), no one would claim that the flag when presented today dehumanizes anyone or is objectively harmful and so should be banned; on the other hand, presenting the Confederacy flag today (in circumstances that are not for historical discourse) is objectively dehumanizing and harmful.
[1]: As the dehumanization of others is part of their core ideology.
[2]: As the dehumanization of others is not part of the ideology (despite its condemnation of certain practices).