Not at all. Silicon Valley tech companies crushed all dissenting opinions online to a comical level. The only place you’re allowed to have a dissenting opinion is in real life
You can find dissenting opinions online. The major hubs are of course the places that the mainstream will claim are full of terrorists and other miscreants, e.g. the *chans and now the fediverse instances that more mainstream ones refuse to federate with. But there are many smaller spaces online, not run by big tech and small enough to fall under the radar of the mob. HN itself does still tolerate plenty alternate opinions.