Around the US, you can still find lots of buildings that have a disused trash incinerator in the basement or out in a back alley. At one time it was common, basically everywhere, to burn solid waste on site.

I think eliminating that practice was both good and bad. Good because burning waste in what basically amounts to a burn barrel with a smoke stack is nasty and produces tons of pollution which has lots of negative health related side effects, among other things.

Bad because it masked, maybe even helped exacerbate, the problem of generating and dealing with increasing amounts of trash. Now, instead of having to choke on billowing clouds of black smoke, you just throw your garbage in a dumpster where it gets hauled away out of sight and dumped in someone else's back yard. That has consequences too. There are mismanaged landfills all over the place that cause lots of problems. But for most people, they're out of sight and therefore out of mind.

And burying trash in the ground is cheap. So much useable stuff gets thrown away because it's much cheaper, in the short term, to just throw it away.

It's shameful. But I don't know what else to expect from a society that primarily runs on greed.

Landfills actually seem to be endorsed by civil engineers to some degree (while also acknowledging that genuine Reuse, Recycle, or Combustion of products would be better)

GRADY (Practical Engineering) has videos on this. Here is one

I can't really remember what i learned from this video though - it might be entirely about the effort it takes to protect the surrounding soil from leeching (chemicals and plastic want to go into the soil and mess it up!). So the sole engineering benefit of landfill might be that it literally fills in places where soil was "mined" to be used as gardening and construction materials.

I think it's quite a bit more complicated than this. The concept of disposing of something always existed, but for most of human history that meant just leaving waste where it fell or at most tossing it at the edge of the village.

It's only once larger settlements appeared that a need to concentrate waste in one location to avoid despoiling the entire area became necessary. This was greatly compounded with the invention of manufactured materials that don't biodegrade like glass and plastic. There was no other solution to this than to concentrate and bury waste so it didn't end up everywhere.