Empirically, probably not. We had lots and lots of content before copyright, and people seem to produce lots of content even in jurisdictions with weaker copyright.
It's kinda amusing copyright always seems to attract discussions about authors rights. It was never about author or their rights. It was and is a set of rules that allow money to be made by publishing books and songs. Authors have a role in that, but so do publishers.
Turns out most authors and publishers suck at their respective jobs. Most books produced by authors are things nobody wants to read. If a publisher's job is defined to be finding works the public likes, they suck at it too. Instead they just publish lots of stuff, mostly at a loss. They make their money from the occasional hit. But only way they can make money from it is if they have a monopoly over publishing it for a while - which is exactly what copyright gives them. Looked at in another way, this "publish lots of stuff and see what sticks" is the way our society discovers what new works are popular. And copyright funds it.
If you take the view that copyright is paying for the discovery and publishing of new works, then consumers paying monopoly prices for 70 years or more is a bad idea. By far the majority of works are commercially dead 1 year after being published. The publishers tend to make their money from the remaining 1%. They might last five years. Very, very few last 20. I don't see how copyright lasting beyond 20 years can be justified with anything other than: "because of the good work he did 20 years ago, he deserves to be paid for sitting on his arse for the rest of his life". In reality, he didn't sit on his arse - he donated to a few politicians - but the outcome is almost the same.
Less of some kinds, more of others. It has been getting easier to create creative works over time, lowering the threshold to make things even for nothing. The netto result would be a bit of an experiment even now, but for sure there are flourishing communities, open source, open content, fanfics, short stories, etc etc. Some hollywood blockbusters even started out as modern internet culture and/or online stories. So there's cross-pollination between the different kinds of communities too.
> It has been getting easier to create creative works over time
When it comes to writing, paper and pens, and then typewriters, have been rather cheap for a long time. Computers made it even cheaper, but it was already so cheap that wasn't the bottleneck. Or take playing instruments, singing even.
But you are totally right about distribution being essentially free now, and with all my qualms about slop and algorithms etc. it's also true that some things become widely known simply because they're really good, sometimes leading someone from rags to riches so to speak, and I can't hate that. I'm sure it would do the same for novels or other "long texts" if more people were into reading those digitally. So while I'd say TV and other stuff killed reading by being louder and more shiny and offering instant rewards, I can't really blame the internet as such for that.