At first, that was really one of my concerns. But then one day my brother and I had a small talk about btc and this concern came up. So yeah, basically we have the same opinion like others here that mining will still continue as there will always be a fee to be paid on every single transaction and that might increase too as there'll be no more btc to mine. And for sure there will be more upgrades to cope with the situation. Btc will never fall apart and its price will then be unimaginably expensive. But then at the end of the conversation my brother and I came up with an agreement not to think of it anymore. Simply because by that time btc have been mined we will no longer be here. Well not unless we made it to our 170th birthday.