The coins/tokens are mined mainly by a very small group - 52 % via 4 main server groups/mining pools forBTC, similar % and 2 server groups/mining pools for Etherium, so not really distributed, the exchanges can and do change the rules if values and thus revenues fall, it will proably take a long time before before the Ponzis and incompetents are removed, total assets in all crypto coin assets are equal, currently, to the asset value of the USA's 52nd largest bank, the volatility will remanin very high for a long time, but Crypto coins may eventually actually satisfy a real world need eventually, there are many fakers and conmen in the space currently - thats without any of the jokes, and they are nicely sarcastic, so it is worth the watch. In short, easily manipulated by a small group of producers and currently with few real world applications other than speculation. You might find his history of Private Currencies vid interesting - historically the US at one point had dozens - UK anti Truck acts of the 1780s prevented this as it was often deemed treasonous to mint coins in competition with the Crown -https://www.youtube.com/watch?v=l7hZjV2rsbQ&t=158s - its 20 mins mind. Sadly no short cuts with Lecturers