That was certainly true under feudalism, which is probably why the modern capitalist center-to-right and pro-labor/socialist left all have roots in classical liberalism.

But as capital has matured, capital as a class has effectively subsumed the landed class, largely by driving land into fee-simple ownership.

Land value taxes are still very much important.

Henry George wrote his analysis not under feudalism, but in the US.

See eg https://www.forbes.com/sites/chuckdevore/2015/07/22/piketty-... or https://en.wikipedia.org/wiki/Land_value_tax