You can participate in Maddof schemes for a number of times until you get burnt. This is the equivalent of "im buying the dip because altcoins are low, and altcoins always come back". Eventually, altcoins will not be comming back, and the tide will finally shift towards natural state of things (total BTC domination), then altcoin bagholders will have their last cry on reddit about how they became scammed by this and that token.
Your sentiments obviously lean in favor of bitcoins and it's influence over the market. I for one do not buy altcoins simply because there price is low but rather for the underlying product behind the technology.
Several shitcoins would fizzle out of the market and not return, but also other coins with real value would speculatively, bounce back when the market takes an upward turn.