The number of altcoins available with greater functionality is on the rise - but do you think they will ever take over?
tl;dr YES.
Fiat (and for this argument I mean the cash in your pocket rather than in the bank) will still be around for a long time, but like cheques which are now an endangered species, fiat will be replace with Bitcoin and some other efficient alts, but most most altcoins will die an ignominious death in the years to come and only a few will survive the approaching asteroid which will ultimately doom them to extinction.
