Bitcoin is already more or less a standard in a sense that other cryptos are often traded in pairs with it, and the situation on the crypto market is largely defined by how good or bad Bitcoin is doing. But if you mean a standard in a sense that cryptos should be backed by Bitcoin literally, then there isn't enough BTC to go buy, and BTC itself is very volatile to be considered for this role. I also don't see why anyone would need an altcoin allegedly backed by Bitcoin if one can simply use Bitcoin itself.