You are correct, the difference i would point to is that sex work is real work and should not be marginalized while spreading mental malware for self enrichment that causes harm to society should be marginalized. This is simply an result of utilitarian calculus to me. If you don't subscribe to that ethical system that is your choice and i am not going to convince you otherwise.

Decriminalization of sex leads to less suffering for prostitues and better health for the customers (they way Germany accomplishes the second thing is not ideal, like requiring even blowjobs to be performed with condoms but that's a tangent).

Criminalization of anti vaccine speech (similar how holocaust denial is illegal in Germany, only high profile cases are really prosecuted) would lead to better discussion about vaccine risks, better vaccination rates, less death and fewer fights within families due to intellectual malware.

I am also for a criminalization of climate change denial as it also a form of genocide denial which violates the human dignity of future generations. Note that in German law statements of facts are exempt from that. Only statements which are univocally false, so they can't contribute positively to societal dialog and deny human dignity to a protected group or statements which are to made to inspire violance against a protected group are subject to these kind of laws. If you say "No jews were persecuted under the third reich" you are commiting holocaust denial. I would propose that "emissions of man made CO2 don't impact the climate", "CO2 emissions will be completly absorbed by more green growth so there will be no impact on the climate" or "climate change or unlimited CO2 emissions will not lead the displacement of people in costal regions due to raising sea levels" can be prosecuted.

Is that a limit on free speech? Yes and i am fine with that as there are positive and negative freedoms. The moment where speech violates the human dignity of other groups of people it should be limited.