People just abandon bitcoin and moving to cryptocurrencies. Why do they need a store of value if they can have both store of value and a currency? So, why should one use bitcoin and not litecoin or monero? The reason?
Reason is not because of people abandoning Bitcoin, no body has moved to other coins because they all were pumped after Bitcoin, all the Bitcoin investors are also alt coin investors, selling Bitcoin to buy alt coins is not abandoning Bitcoin.
Because public invested in bitcoin brand so much?
Because if you have a decentralized currency and have everybody accepting it, you don't need any other currency, moreover, if you have a payment processor accepting 75-100 different coins, you could use a coin with low fees and fast transactions.
Btw, I think that I was one of the first beggars to use a Segwit address for signature payment. (note, as the rule of a man has got to eat applies here, merit me for I am begging for it).