Bitcoin does not have to depend on altcoins to make progress in cryptocurrency while altcoins will have to rely on the performance for bitcoin for them to be able to make progress, just as we know bitcoin to be the leading currency in cryptocurrency, it leads while others follows, maybe we should also put it in this way that its because of some of the shitcoins in altcoins that makes everything appear the way we see it to be hard in trusting some coins.
Sorry but I think you are wrong, like the topic of this thread says, bitcoin needs Altcoins, as much as Altcoins needs bitcoin, this is a complete fact, because judging from scalability issues with the bitcoin network, if bitcoin was the only crypto crypto currency around with a market cap of the ganeral crypto market currently, then trust me if I tell you that Bitcoin will be unusable to many, in fact, cryptocurrency may never be adopted because...
1. The price of bitcoin will be way too expensive for many to buy and hold it.
2. The bitcoin network will be ultimately unusable due to extremely high cost of transaction, because there is no way the number of people in crypto today are all going to be buying and selling only bitcoin, and the bitcoin network won't be super congested.