Slippery Slope isn’t a fallacy. It’s literally how things progress from good to worse.
Identifying early signs of Stalin’s rise to power would be called Slippery Slope these days.
As for twitter, their focus removing on information that is damaging to people in power is concerning. These days private corps wield as much or more power than governments.
I don't think that there is any in Stalin's rise to power[0] that would fit the definition.
The post you are responding to also refers specifically to the Slippery Slope Fallacy[1] which is a different beast than just calling something a 'Slippery Slope'
As for twitter, their focus removing on information that is damaging to people in power is concerning. These days private corps wield as much or more power than governments.