You are correct to use the word tyranny. Socialism sounds so social and friendly, doesn’t it? We need to use the words tyranny and tyrant more often, when we talk about the daily encroachment on our liberties.
It is the nature of socialism to devolve into tyranny -- if it doesn't start that way.
How many times has socialism simply been the excuse for a brutal dictatorship? Do Hugo Chavez, Fidel Castro...Vladimir Lenin ring a bell? The supporting philosophy, after all, refers to the first "post-revolutionary" stage as "the dictatorship of the proletariat". But, somehow, the state never "withers away".
The simple fact of the matter is that people don't want to behave the way socialists demand they behave. Therefore, "for their own good", it is necessary for the state -- and its enabling officials -- to employ coercion to achieve the outcome they desire.
My little sis, a social worker, claims she is a socialist (she isn't, not really). But she instinctively considers herself the arbiter of what is right and wrong in other people's behavior -- she willingly runs the lives of others (her clients). And would love to punish "the rich". Just because...
Like I said, a socialist is a natural totalitarian.