The game (as it were for better words) will continue for a long time. Whenever a danger is on the horizon updates and upgrades will be made. Just imagine if Bitcoin mining was resistant to these miners, the overall supply would so low right now and there still would be significant scope for growth. Mass mining Bitcoin using farms was something that maybe should have been blocked a long time ago but probably even now developers never see it as a threat of a different sort which allows conglomerates to mine and profit from Bitcoin on an industrial scale.
That's the 'Bitcoin Game' and that cycle will never end. All "lost" coins in the old system will be activated in the new system. The first change to quantum resistant system will activate all lost P2PK coins. The next update will be a change from hashing system and will activate all lost coins, and so on.