Bitcoin price fixation didn't happen after $12k. Actually btc price rally started from there and bitcion marketcap dominance have increased enough since then. It was staying above 70% for a good period of time. Though it has dropped under that percentage in recent few days and altcoins marketcap increasing now. I think bitcion price really will start again soon, like before. And alts willl move slowly behind it.
Alts actually do not move slow, they do increase in fiat a lot faster as well, it is the public that has alts in bitcoin form that are upset about the situation. Let's assume that you have 1 bitcoin that worths 10 thousand dollars, and instead you buy altcoins with it, a year later your altcoins worth 0.5 bitcoins but 100k dollars, would you be upset about it?
Basically people want to see altcoins to worth the amount they used to worth, but looking at ETH for example, it was 130-140 dollars a year ago, now over 1k, did bitcoin have the same type of increase? It didn't, that is what I am talking about as real increase.
People think alts are not doing well because most of them dropped in bitcoin price, and many believe "if I kept bitcoin instead of alt, I would have been richer" but they do not realize that they got richer anyway, so whats the purpose of this complaint when you are already richer.