I ran a lbry seeder a few months ago to practice devops & data science.
The lbry crypto is used to hold links to every bit of content uploaded into the network, boosting content on the platform, enforcing channel names, creating paywalls for certain content on the platform, & tipping creators.
The blockchain network’s primary goal is to hold a long list of in network links that correspond to content stored on individual computers, so when you put in for example lbry://fireship#f/Java_for_haters or something like that, iirc (I’m not near my PC rn), the request goes to delegation servers which query the block chain, return the video link and then call devices on the BitTorrent lower network to send over the requested blobs.
I may be wrong on if the delegation server or the block chain is queried first, but that is basically how it works.
As for moderation/censorship, this is done on a web server built with the lbry apis delivering the videos to the client. You basically can Blocklist individual links or entire domains per se in the bc network so they will not appear on your stuff. This is how they get rid of copyright infringing stuff. Use a different client & change the moderation server and you will see videos odysee.com blocked. I believe you can setup a whitelist too.
Finally, I don’t think comments are actually built into the library protocol itself but are still managed in house by lbry/odysee inc itself. Would have to look deeper into this one, but it wasn’t baked in last time I checked.
The lack of moderation isn’t due to the lbry protocol, it’s the deliberate decision of the lbry team to avoid doing anything as much as possible to show a contrast to YouTube.