50yrs ago, corporations and narrow slivers of the US who controlled their editorial boards (e.g., those in NYC or LA, to some extent DC) were the only ones with free speech. They didn't "silence" anyone, they just didn't give them a platform at all.
A stark example is police brutality and BLM movement -- this is not a new phenomenon. Except the media (including liberal media) chose never to cover it in a way where real change could happen. The extent of police brutality only entered the realm as a serious issue once the other half had sufficient freedom of speech to talk about it, gather around it, and bring it to light in a serious way.
This is the success of "the hashtag" and new media in Silicon Valley.
50 years ago nearly all broad platforms for spreading ideas were owned by corporations run by very few individual people. Lacking a platform was the default, the vast majority of people were "silenced" in the sense meant by the modern "free speech" (really compulsory association) movememt.
The government was always trying to silence people though, see McCarythism and Vietnam war protests.
I do not think attempts to restrict speech are very new.
I think the desire to restrict other peoples speech is relatively new because the internet was relatively new. 50 years ago, you didn't see corporations able to effectively silence people as much as you do now.
A more accurate quote for todays crowd may be "I disapprove of what you say, and I will fight to the death to stop others from hearing you say it."