I just want to find a secure and decentralized alternative to bitcoin
Which blockchain could become just as decentralized as Bitcoin?
Where could I store my assets in an emergency if there are no more bitcoins?
I don't think that if bitcoin disappears then there will be other coins persists because during Bull and bear season the price of other coins are regulary fluctuates according to the ups and downs occurs in bitcoin price.
Bitcoin is a successful coin you must choose bitcoin but if you doubt that someday bitcoin will not be here to give us profit then you can choose gold because if bitcoin become disappear then all other coins will surely disappear too but gold is not related with bitcoin.