Bitcoin scam or easy money?

Most of those are ponzi schemes (Similar to BitConnect I'm assuming) and if you mean trading then that is entirely market pyschology and luck, there are no guarantees on whether the price will go up or down but if you know how to read the market and you consider the news you will be able to make educated guesses. Also, if you own most of the market share you can easily manipulate it in an endless cycle. If you own most of the market share and then sell, it causes the price to dump/"correct" itself due to demand and supply by increasing the supply in the market drastically, however the demand remains the same so the price decreases. This results in news outlets reporting that the price is going down or crashing etc. which results in unexperience traders selling due to them being scared, and whenever you think the price is low enough, you buy a lot more of that same currency to take it off the market which causes an increase in price and news outlets reporting it causing unexperienced traders to buy again. It's a vicious cycle that wealthy investors are able to enjoy. If you are able to read the charts or get information, you'll probably also be able to make money off it.