This is an interesting question. I have actually encountered the use of "lands" in the plural noun form.
One such usage references holdings in land, and is almost always in a formal context pertaining to a national or governmental land and estate planning office, department or service. It seems to be perfectly valid usage in this context, even though "technically" land is considered to be uncountable in this sense.
Examples of such usage include these from Canada:
This from Kenya (a former British colony, so this is unlikely to be a simple grammatical gaffe):
And this from Hong Kong (again, a former British colony with a high standard of formal English in official contexts):
Dictionary definitions mentioning this specific usage are sparse, but I managed to find a couple:
holdings in land
c. lands Territorial possessions or property.
Personally, if you were to write a sentence like "He was extremely wealthy, with many lands to his name", I would consider it perfectly acceptable usage, as it implies that he owns many distinct plots of (non-contiguous) land. This is in contrast to a sentence like "He has much land to his name", which could just as easily mean that he owns a single (contiguous) large plot of land.
Another context I've encountered the word in, is in the sense of multiple nations. For example, "People of Many Lands" was a BBC school TV series broadcast from the 1950s to the 1970s: