"Is that really that value that governments should be optimizing for? What about people who's content isn't all that good? Should they be ensuring payments for anyone who creates a new viral meme?"
That's exactly what government should do. Let the market to decide what content it perceives as good or not. The viral on its own means that the content is desired by some in the population. You or I may question its quality, but that doesn't discount its value to the ones who enjoy it.
I think that's where it should stop. Government shouldn't censure content (up until is outright harmful to the society [there are mechanisms in place already to deal with this]).
The curation should come from the platforms. Platform can compete for the eyeballs by picking the content they want to distribute. However creators, whoever they are, should be fairly compensated for it.
My point was that ensuring people get paid is not what our end goal is. We should identify what our end goal should be and try to see if a different tactic might accomplish that goal better (with less collateral damage).
For example, people who create memes (the actual memes, not the images that later become memes) are motivated by social acknowledgement. Same goes for many Facebook posts.
Mandating payment systems is unlikely to motivate those types of content creation, and may in fact suppress many other types.
However, creating content based on social rewards (like most social media sites currently do) does help the creation of popular content.
The case you described is already covered (at least in US) by the Fair Use doctrine [0] and works, well, works ok. I don't think the government should consider the use case of copyrighted work.
Is that really that value that governments should be optimizing for? What about people who's content isn't all that good? Should they be ensuring payments for anyone who creates a new viral meme?
I'd propose a different value: "How do we best incentivize people to produce content?" (or perhaps "quality content")
Trying to make sure people can get paid is one strategy to incentivize the creation of quality content. But when you rethink of the problem in terms of optimizing for the production of quality content you can think up other strategies as well.
For example, Facebook and Twitter have done a great job of encouraging people to produce content (with questionable levels of quality), without attaching any monetary rewards to it.
Reframing the question in different ways will help us arrive at larger variety of solutions.