I think the same principles hold true for earthen terrain

Some of the points I made about the moon only really hold for landmarks specifically on Earth, with the moon as sort of a trans-geographic landmark. I do think we should avoid burying people in the Grand Canyon and things like that for a similar reason, they are part of our cultural heritage and don't need to have corpses piled on top of them.

Being merely a stretch of field with no particular significance is not the same thing and it does not pose the same problem, though burial universally poses the issue that our space is finite and we should really be seeking to optimize it for those who are alive and those yet to live rather than those who have already stopped living. Not that we should be digging up grave sites, but we can eventually stop expanding them for the most part.

So yeah, I think we agree, humanity should move on to cremation (and other practices like sky burial) should become near-universal, with possible exceptions for bodies that are specifically worth studying being preserved to facilitate that study, along with the general supply of cadavers for med students, etc.

As a final elaboration to add a bit of optimism, I think that burial generally wouldn't need to be "violently suppressed", because if cremation is what is normalized and there aren't really avenues for securing a gravesite like is conventional today in the US, people will just go with what is available to them and only a scant, scant few will be trying to pull off reverse-heists to illicitly bury someone, since they know such a body can just be exhumed and thus that they would probably be undergoing significant risk to make what is functionally a very poor grave.

Edit Thinking about this issue, I was reminded of a poem: