That comic deliberately mis-interprets and contradicts itself to make a point.
For example, it quotes Mill's comments on the necessity of protection against the "tyranny of prevailing opinion." However, that doesn't mean freedom from consequences, it means that anonymous speech must be possible and protected.
It mentions "liberty of circulation" and "access to infrastructure" for minority opinions. That doesn't mean that Twitter has to host your bullshit, it means that the government shouldn't ban you from using public roads to deliver your controversial newsletter. If Twitter were part of the government you might have a point, but it isn't. At most, you could argue for net neutrality giving everyone equal access to the network in order to host their own material.
You can also argue that public infrastructure should not be privately owned (WARNING: socialism!) because private companies are not the government. So it sounds like the comic is arguing that Twitter should be nationalised and run as a government service.
The last two panels argue that minority opinions should be considered. I agree, as does Mill. However, that doesn't extend to being require to give them a platform. The "responsibility" to extend free speech rights to others only goes as far as not not silencing them through the government (e.g. with laws), it doesn't mean you have erect a platform for them to speak from in your garden.