Nothing in this world is permanent, and that's going to include Bitcoin. I'm sure it's going to take more than a dozen lifetimes for something so great to be invented that could potentially replace Bitcoin though.
I guess as long as computer and internet are existing the bitcoin will remain. So I think computer and internet are forever be.so for me bitcoin will be fotever be...just my opinion
Of course, Bitcoin will be forever, as long as know how to protect it, you can even transfer it to your kids as an inheritance. What's holding Bitcoin spot though is that it is the prime mover, so it can stay at the top for many years until someone replaces it. That's what human history tells us, you can remain on top, but we don't know what the future will bring. Maybe some new crypto suddenly emerges, then a total shift from investors.