In short, it's a classic example of something trying to be made more accessible and less constricting for the sake of more detailed and in-depth feedback, only to be abused by a segment of the population who could care less about any of those things.
I've gone back and forth on how content producers will disable comments on their respective journals and channels. Some time ago, I stopped allowing anonymous comments on my entries, not due to trolls or spam or anything like that, but something surprisingly more annoying: feigned authority. Put simply, if you're going to claim expertise on something, stand by what you say.
Remember Rob Granito? Neither do I.
In all seriousness, Granito claimed to have worked as a ghost artist in the comics industry for a number of big names. When a blogger called him out on his lie, by way of being on a first-name basis with the editors at Marvel and DC, none of whom had ever heard of him, a poorly-written comment appeared on the entry from an anonymous user, insisting Granito was "legitomite (sic)." Sure, it's rather hilarious someone would be that delusional, but
The fact is we could probably go on for hours about all these "gatekeeping" tactics employed when it comes to comments, be it Xark, Atop the Fourth Wall, Go Make Me a Sandwich, or forums on The Spoony Experiment, but one simple fact is constant, regardless of how it may seem otherwise.
YOU ALWAYS HAVE OPTIONS.If I see a video on YouTube that I really like and want to talk about it, such as a short film I want to give a scene-by-scene analysis, I could try and fit my remarks into a 500 character comment on YouTube itself, wherein it can be replied to and voted upon by potentially anyone else visiting the video's page, or I can link or embed the video on my Blogger or Tumblr page and avoid the character limit at the expense of making the voting and reply options a tiny bit more obfuscated by comparison. Indeed, this has often been a sort of proposed solution by the likes of Feminist Frequency and Xark for their more civil readers following their respective influxes of trolls and cyber-attacks. Critics have called these moves cop-outs against taking criticism (Want to leave a comment? Jump through this fiery hoop!) or ploys for getting more referral traffic (Want to leave a comment? Be my billboard!). As valid as these criticisms may or may not be, I find it nonetheless funny that so many people take an "Us vs. Them" approach, treating any change in the rules as some sort of unfair handicap. Really, all it's doing is decentralizing the conversation from one in metaphorical earshot of the original post and more public to one on your own personal page with any ensuing discussion being mostly private. To put it another way, you can picket or you can petition. You may have more experience and possibly better luck with one over the other, but the task of making either option work best for you is yours alone. You have only yourself to blame for not being heard or taken seriously.
In short, no one has taken your right to speak away from you. All that's happening is that you need to exercise those rights a little more responsibly and make the most of what you have. If that feels like defeat or oppression to you, then you probably never took your right to speak all that seriously in the first place, if not had an utterly naive understanding of it.