Bitcoin will not remove Altcoins. It only happens in some countries that grant permission to use Bitcoin as a media transfer. The altcoin is an alternative to Bitcoin, so the presence of Altcoin has given many colors. Anyone who trades cryptocurrency is not only on Bitcoin, but they can also trade using altcoins.
Until now, Altcoin continues to grow, so that if Bitcoin wants to remove altcoins, I think the one deleted is an Altcoin that is no longer developed or has no selling value.