You can get banned here for similar reasons as you'd get banned from things on Reddit. In theory the federated setup helps to mitigate it somewhat, in that if you get banned from your primary instance you can hop over to one that's a bit more agreeable to your perspective and continue on.
For example, I was recently banned from LGBTQ+ on, I think the world server, cause I posted a fairly benign straight opinion to a post that had an image basically asking for cis commentary. It had like 5-7 upvotes, about 13-15 down votes at the time the mods kicked me out -- so even amongst the community it was a bit wishy washy, but the mods still opted to take action. On Reddit, that might've gotten me flagged / banned site-wide, depending on which White House narrative the company is marching to on that day. Here I just lose access to the LGBTQ+ community, shrug at them echo chambering up, and continue about my day.
In terms of "Why do we only control the speech of leftists", I imagine it's because the threads you continue to access are left leaning -- meaning those left in your bubbles, are the left-leaning sorts saying they'd been banned. Right leaning comments, and even (in my view) some centrist / neutral comments, still get people banned. These days we all basically have to assume that there are companies / algorithms creating bubbles in online spaces; you need to temper it with a good bit of secondary sources outside of 'social media' to get a more accurate picture of people's mindsets/trends. Eg. Social Media + direct views of national/local news paper sites + in person discussion with various sorts.
Canada ought to invest heavily in vaccine tech / bio firms. Even more so with the states not doing so.
Most obvious reason being basic health concerns, and the response required for things like pandemics, which are likely to increase in frequency as the world burns to the ground. The less obvious reason is that those assets / skills double as bio weapon developers (as we're seeing practically everywhere, things like the Geneva convention / anti-genocide stuff has become very flexible). All the talk about getting nukes is silly, when you can quietly have a team of 2 dudes in an off-grid forest hut, with a chicken coup and a couple drones, potentially do billions of dollars of damage to a country that is... in a rush to further expose themselves as vulnerable to this sort of threat, by firing all their researchers/scientists on the subject.
So we can invest in biotech for generally altruistic and proper reasons, while having a very easy to conceal / clandestine alterior motive that can serve as a bit more of a deterrent / safety net. Win-win.
Sorta like how we ought to roll our climate disaster response teams under a military umbrella, and jack up our spending on things like logistics teams for moving things in and out of disaster areas. We need to hit 2% or 5% GDP spending on Military for Nato? Don't see why we can't meet that target with ease, just by spending more on our own natural disaster response capabilities at the federal level. Can even lend those assets out to assist our allies when they get hit with issues. Again, win-win.