That's certainly true, altcoin narrative shifts every cycle and there's always formerly top altcoins that become abandoned and unused eventually have zero trading volume as well as close to zero on chain transactions and there's new altcoin that's hyped up.

BTC has been here for quite sometime and from the dominance alone it seems BTC just occasionally dominate the market then there's time for altcoin rotation, for the people who seek more profit and for the most part it has nothing to do with all those dead altcoins.

Altcoins should be more concerned about other altcoin taking over their position.