The internet is undoubtedly a huge boost for freedom of expression, and not only a quantitative boost. It has certain qualitative characteristics that older media don’t have, which make it particularly beneficial for free speech.
A first reason why the internet promotes free speech is its relative cost: it has made speech much less expensive. You even don’t need to own a computer since you can, with relative ease, use a public one. And even the cost of a computer pales compared to the cost of many older media.
Another reason is that governments find it much more difficult to censor speech on the internet. Speech is no longer bound to a particular carrier which can be easily confiscated or destroyed, or to a particular territory where a state can exercise its power. People can publish on websites in other countries without being there. Of course, governments do retain some considerable censorship power over the internet, as is demonstrated by the case of the Great Firewall of China, but it’s safe to say that this power is relatively weak compared to government’s powers over traditional media, precisely because of the international character of the internet.
Unfortunately, we see that private actors sometimes replace the government as censors. The discussions on net neutrality for example result from some cases where internet providers have blocked access to competitor sites or favored access to friendly or related sites (see the case of Telus blocking access to a labor union website). One could also claim that Google, for instance, despite the good it does for free expression, also in a way limits it, since it systematically channels people towards speech that already has much exposure and freedom, and “buries” all the rest (read more about this here). There is still domination and inequality on the web; the question is whether on average the internet has done more to limit it or to advance it. I believe the former.
A third reason why the internet promotes free speech is the gradual disappearance of middle men. You don’t need editors, publishers or peer review to publish your views. In traditional media, these middle men normally filter out a lot of speech, often to the benefit of the public but never to the benefit of speech.
So these are three reasons (among many others) why the internet expands the amount of speech and promotes free speech in a quantitative way. But it can also be argued that the internet has improved speech in a qualitative way. That may be a counter-intuitive claim, given the amount of bullshit that’s present on the web, and yet I think it’s true for many pockets of the internet. Because the internet creates a quantitative boost for speech, it also produces a qualitative one. The internet has allowed more people to speak, listen and discuss, and it’s a common argument in philosophy that widespread participation in discussions tends to improve the quality of people’s opinions, under certain ideal circumstances. I won’t make the detailed argument here, since I’ve done that many times before. In a few words, the argument boils down to this: the freedom to speak, the equal freedom to speak, and massive use by large numbers of people of this freedom, result in the appearance and confrontation of a large number of points of view and of perspectives on issues. It means that a proposal or opinion or policy is subjected to intense scrutiny and criticism. If it survives this, it is bound to be of better quality.