What makes a project decentralized:
1) Is the creator known? Yes or no
Identity of Bitcoin creator Satoshi Nakamoto is unknown and Bitcoin has done pretty good so far and it is most decentralized project in the world.
There is no office for Bitcoin to raid and arrest stuff, so that is obviously a good thing.
2) how are the coins distributed? (Obviously the less spread out, and fewer large bag holders the better)
Fair distribution is very important, and there should be no premine or presales we see with so many scams.
3) number of full nodes being run? (The more the better)
More nodes network have it is going to help decentralization especially if they are distributed between many countries of the world.