In vain I bought it for $ 500, now I do not know what to do with it
imho, cut your losses and sell it but keep an eye on the chart, in case it goes into a pump. You could buy quick and sell higher to make less loss if you have that kind of time.
Keep only what you can afford to lose. I bought enough at $500, and will hold as a hedge against a bad event in BTC. If cash fails, then so be it.
I did the same with ETC, knowing that ETC would most likely fail, but on the basis that a division of investment between ETH and ETC would give a spread of risk.
It is always about the developers first, and the community. The chains with the greatest agregation of development talent will have the best and most relevant tools and software. Community and distribution are important, but they tend to grow from the development ecosystem.
The effective airdrop in ETC and in BCash provided a starting distribution, but it was only a snapshot, and will likely be siphoned away slowly by the gravity of the system with the greater mass.
The conclusion so far is that Core is the winner. Relative price movement will confirm that, as it is doing right now.