LotR -- Book 6 - Chapter 3 - Mount Doom

[Kuruharan]

it is that Eru intentionally kills him when he wouldn't otherwise have died. Gollum's death is not a result of natural causes, but of the will of Eru.

And all this other natural death is built in by ????

by His destruction of the Numenorean fleet Eru takes away Men's freedom of choice.

No. It is imposing the consequences of those choices. I don't seem to recall seeing anything about there being no consequences to actions.

And it is not like the Numenorians had not been warned...repeatedly.