Sometimes markets rise. Sometimes markets fall. It is what happens every day on every coin, asset and stock exchange. Traditionally when BTC rises, most of the rest of altcoins fall. Nothing misterious here: the amount invested in cryptos by traders is what it is, and if a trader wants to buy BTC, he will need to sell his altcoins.

You can be sad or unsettled because the price is not the one you want. But claiming that a fall in price is due to a scam like that user said, or you quoted and said he was right, is simply FUD and it is out of place in this forum unless you have proofs to sustain that.

If you need a hint of what is going on, check the rest of Alts: similar trends. Check Bitcoin: opposite trend