Any coíin is only as good as the comunity is going to suport it.
Take an example if today the possibylity to mine btc will end ppl will try to find an other alternation.
Despite the original idea of bitcoin as a digital curency , the bitcoin is only as strong as there is the possibility to make profit with the mining.
U can see that because of the perofitability of mining btc there r still growing manbufacturers willing to offer new more powerfull mining equipment.
But when the difficulty of mining reaches the top possible where u dont get any proffit of it. The btc will probably die.
And all miners an manufacturers will turn their attention on next most popular coin type.