Is it really not matters if you attain oneness or not?
Well this is for only those who have developed the state of oneness already and who already become what they already are.
In short yes trying to attain is useless. It is as same as a male trying to be male and a female, or a rock or tree trying to be themselves.
You cannot try to become which you already are. Then is Knowledge is also kinda a useless? Yes from the perspective of Exsistence knowledge is totally useless which have no use at all.
Onces your ignorance remove you don't have to stick with knowledge of oneness at all. Because onces you become one with whole there will be nothing to achieve. So trying will shift to being.
Being and trying are two different things.
Attain oneness is useless for those who have already attain it. Ask them and they will say that there is nothing to attain at all in spirituality. But a person whose eyes is covered with ignorance can't understand this.
For such reason knowledge of oneness created. The sole purpose of this knowledge is to remove ignorance not to attain something. So we are leaving here, not attaining something.
This path leads to destruction to old ignorance, old fake belives. As I said one of my reply to someone spirituality isn't all about fruitful it is very heavy and burden especially for ignorant people. For a seeker detachment is good and they loves to being detach and being one with everyone. They treat everyone as same. This is called true love. Love - giving which you have ability to give. We don't take we give this is majority of the nature of spiritual beings.
We give you yourself which in result comes as detachment and love.