If it's leaking toxic breakdown byproducts out into the water table or something then that's an issue, sure, but "things going to landfill" seems to be treated as axiomatically bad by most people.
Landfills take up a lot of space. I saw a documentary about it (forgot the name of it). Humans waste so much and the trash keeps piling up. You can only dig so much.
At a depth of 400 feet, the entire US annual trash output is approximately 1,000 acre [1].
There are 37 billion acres on earth. And indeed, much of that is not very habitable land.
And importantly, landfill space is not permanently lost. There are many beautiful parks around the world built atop landfills.
[1] https://science.howstuffworks.com/environmental/green-scienc...
Also, the waste can pollute underground waters, and if there are many rivers in the region, the water will be contaminated in a large area around.
Most people's conception of what land is available is limited to their local metropolitan area, and they have no idea just how abundant land is in the hinterlands. You could probably bury all the nation's garbage in the craters left inside the Nevada Proving Grounds, which is a radioactive wasteland anyway. And shipping contains of garbage 500 miles from LA, Vegas, and SF to Northern Nevada looks a lot more appealing when you've gotten used to shipping it 10,000 miles to China.
Is that really true? At least for CO2 emissions, other sources seem to imply the opposite, with ships being much more efficient than trains: https://truecostblog.com/2009/11/23/is-local-really-greener-...
Dutch trains run on sustainable power.
https://www.ns.nl/en/about-ns/sustainability/energy/sustaina...
https://bigthink.com/politics-current-affairs/india-trash-mo...
This is simply not true. Landfills don't take up much space, we have plenty.