Learn English – Have you joined *yet*

Though the complex preposition of off of is widely used, one may argue that it's redundant.

Here is the Oxford Dictionaries' reference:

Off of is often used in place of the preposition off in contexts such as she picked it up off of the floor (compared with she picked it up off the floor ). Although off of is recorded from the 16th century (it was used by Shakespeare) and is logically parallel to the standard out of, it is regarded as incorrect in standard modern English.

Now, about the point

someone got a point - someone got an idea to think upon

The key lies in the context given prior to the quote: Lord Wedgewood alleged that Britain had reneged on its commitments, and then he spoke the quoted phrase with bitterness. He is disappointed with how things have turned out so far. But even though he is disappointed, in spite of his disappointment, he still hopes that he will see the outcome that he desires eventually.

Thus definition 3 at your link (3: In spite of that; nevertheless) is the relevant meaning.

The statement is a rebuke of Britain's inaction; it says "Britain was supposed to do this good and necessary thing. Britain failed. But I still have hope that someone else will step up and do it." But if we leave out the yet, it takes away some of his bitterness, turning the statement from a rebuke into a much more neutral call for action, saying essentially "here is a good and necessary thing. I hope someone will step up and do it."