I'll take your word for it..................who will replace Vera Lynn then......I think where you might be mistaken is in assuming that there is only a finite number of species that ever can exist during the lifetime of the planet.
It's not a case that 99% have become extinct, leaving just 1% and that 1% will get smaller as more species die until there's none left.
It's a case that as one species dies out another replaces it.
It is likely that there will always be a rolling 99%/1% ratio, since the planet can support only so many species (for various reasons) at any one time.
That's what evolution is all about - as the environment changes so do the species inhabiting it. One species may die out but another replaces it - leaving us with a ratio of roughly 99%/1% (actually, by the very nature of the maths, that ratio will change - but during our lifetime it will appear about the same compared with the time span of the Earth).