As long as mining is profitable and the costs are reasonable, if we keep going like this then it wont last for another 8 years, imagine how many miners will be needed to mine by the next 2 halving? would you buy 100 ASICs to mine half a Bitcoin in a week?
Mining could maintain profitable or not. But the lasting time of bitcoin is not directly dependent on mining. The usage and demand are much more important.
I think this question is now more important and significant as how long will bitcoin will last in its original form or are we splitting it up making two chains and creating a whole lot of confusions. I hope soft fork is activated and there is no two chains of bitcoins. If this happens bitcoin price will rise to nearly the double, making it good for everyone.
bitcoin stopped being in its original form a very long time ago! what we know as bitcoin today is different from what Satoshi created. it has evolved, there are so many fixes, so many improvements so many additions,...
and it will never end. it should never end actually. bitcoin needs to evolve and adapt with the future like any other system.
and we are not splitting bitcoin, some group of people wanting to take over bitcoin and possibly even kill it (government conspiracy or banks) are trying to do it.
and with bitcoin i really don't think 2 chains can last. there will only be 1 bitcoin that can gain the support and economical value.