Bear in mind we can used any words to describe things to understand easily but it doesn't necessary mean it is. Nobody can count sands in this world but we can assume using bitcoin transactions as sands which could possibly mean tremendous transactions.

That is just a representation of 'how much' really means for bitcoin, though one can never actually count the number of sands around the world. 2^160 still is a stagerringly huge number, and relating that number to the number of sands for the number of possible addresses in bitcoin, I think, is not exaggeration but a just comparison between two relatively uncountable things. I know they have placed a definite number to work with in generation of addresses but seriously, who would bother getting all the possible combination anyways?

I believed the statement which was made by the experts in subject was right, it might be overstatement though but if we look at it very well, it truth and I'm sorry if what I said break your heart because no one can know the actual numbers of bitcoin address. Besides, wallet like electrum, bitcoin core had about 32 addresses and if we account the number of this wallet users around the world not to mention exchanges wallet address we definitely cant know the whole all total numbers of the bitcoin wallet addresses out there.

i dont know how many sands on earth, as i know that if you want to generate the same address (to get the same address on second generate) it will very impossible, because ive read an article you need hundred years with the fastest computer right now. so i think it will very impossible to generate same address twice

I am pretty sure that is completely wrong. As we know, there are around 32 million bitcoin addresses. Accodring to National Public Radio, there are around 7.5 x 10^18 grains of sand. This means that whoever said such bullshit was wrong for more than a billion. Quite a huge mistake, if you ask me. Such comparisons don't make sense anyway, because a grain of sand is nothing and bitcoin address has certain meaning and purpose.

The statement does not suit right with the term used to describe the number of wallets that were into usage. Every user will be having more than one wallets and upon the same it is not possible to calculate the total number of users in cryptocurrency. More and more Blockchains was under development and those will get interconnected in the future and the same at any cost won't defeat the count of the sand.

There are 32 million addresses WITH a balance.
God knows how many addresses are in wallets with a balance but have never been used.

The OP is talking about the number of possible addresses.

Who are the experts you are talking about, what ever may be the situation, it is really hard to accurately estimate the number of bitcoin address in existence, presumably there are about thirty million active users in the entire market and i am not sure how you can evaluate the amount of wallets in existence and even if the entire billion population starts creating address we will still have more of them available and if there is an address collision we will have a solution for that too with longer bit number, but you cannot compare it with the sands and dusts and from next time onwards, reveal the name of the experts. 

The number of possible bitcoin addresses is absolutely greater than the number of grains of sand on the planet. Current estimates of grains of sand on Earth is in the region of 10¹⁸ - 10¹⁹. Taking the higher end of the estime, log₂10¹⁹ = 63.1. 2⁶³ isn't even remotely close to the number of possible bitcoin addresses at 2¹⁶⁰. The estimates for the number of grains of sand could be out by a factor of billions or trillions, and still not even come close to the number of possible bitcoin address.

Hell, the number of atoms in the world is estimated to be somewhere in the region of 10^50. Log₂10⁵⁰ = 166.1, which is pretty close. In fact, 10⁵⁰/2¹⁶⁰ = 68. So the number of atoms on the planet is only out from the number of possible bitcoin addresses by a factor of around 68.