Probably the former, given the hysteria about running out of landfill space was partially the reason why there was a push to recycle in the 80s.
>GONZALEZ: There were all these stats coming out at the time that showed that the number of landfills in America was plummeting. Landfills were closing, and people kept citing these stats in stories about the garbage barge.
>KINNAMAN: And so people put it all together, and in their minds, the conclusion was that the United States is running out of landfill space. The United States was full - that we couldn't store any more.
>[...]
>GONZALEZ: OK. Here's what else was happening at the time. Yes, landfills were closing, but that was because there were new rules for landfills - stricter rules to protect the environment. The EPA said you now have to do things like line the bottom of landfills with plastic so they don't contaminate the groundwater.
>KINNAMAN: And so the old town dump - every little town had one - was out of compliance. You can't accept garbage in here anymore. It's illegal. And so these town dumps were closing by the dozens.
>GONZALEZ: But in their place, regional landfills were becoming a thing - bigger landfills that could accept trash while still following all of these new rules. The Natural Resources Defense Council says there used to be about 10,000 dumps in the mid-'80s and that now we have less than 3,000. But we were not running out of space then, and we still aren't running out of space. Thomas says we probably have thousands of years of landfill space left in the U.S. And even hardcore environmentalists reluctantly agree that, yeah, we have a lot of space left. But people thought we were running out of space, and that was what mattered.
>KINNAMAN: And so the recycling era was born. This is when state government said, we're going to require cycling to - recycling to occur.