"speculation" will ensure its survival, how?

Lets assume btc crashed dramatically (99%) .... many will sell BTC, many will stop mining, many will stop building .... a dystopian type of reality....

There will be ones who are still there betting on the future, "speculating" on its future price... that last wall of defense will eventually lead to more and more people coming back to the space ..... TLDR there will always be believers :)