I often think about this endless list of things we "can" and "cannot" talk about, what's correct and what's not... and how it sometimes feels like the people who are going on and on about so-called "tolerance" are often quite INtolerant. A local friend of mine refers to it as "weaponized political correctness."
As you suggested, the practice of NOT talking about something does not magically make it go away.
Yes, political correctness has been a scourge on freedom of speech for a long time and has been used as both a control and defense mechanism.
Speak up, speak wide, listen closely.