I have given this two stars. I'm not sure why because I absolutely love Beckett, despite being at complete right angles to his philosophy. It could be that. Or it could be that, like modern art, one could point at it and say, "A three-year-old could have done that!" Which is sometimes true. But not generally.
Beckett's work is nihilism. It is a statement of nothing; I would say an "incarnation" or "apotheosis" of nothing, but that would be a contradiction. Don't try to read a deep meaning into Beckett's plays, because you won't find any. The reason is quite simple. There isn't any. Beckett isn't poking fun at those who think there is, as that would be to say something. I would say this is the "whole point", but there isn't any point for it to be the whole of.
However, all this is nonsense, because there is actually a lot going on. There is darkness, confusion, pain, power, cruelty, and loss. There are hints of a half-remembered past flitting away as the horror of the present presses forward into the dimness of the future, all to be consumed by the cruel tyrant of... nothing.
This is the situation in which, he claims, we all live. This is all that we have, and that "all" is nothing. We all live on that stage, in whatever absurd and dismal situation, watched by the confused who cannot see themselves in the playwright's mirror, because all they have seen hitherto is a distortion. Or perhaps they are surprised that all they can see in that mirror is nothing.
Don't go calling this, or any part of it, a masterpiece. A masterpiece is something; it is an achievement, and to call it so would give it a false meaning, as if you or your opinions were more than nothing. Don't call it genius or witty. Just call it, no more a waste of time than any of our other diversions, when it will all come to nothing.
Depressed yet? Oh, no. You wait until you start reading it...