No, they are not. That is why I showed you the geometric series, which is an infinite series of positive values that add up to a constant, even if you keep adding FOREVER.

Saying that more and more bitcoins get lost does NOT mean that the number or ratio of bitcoins still in circulation goes towards zero! Not at all. That is the point. It might mean that, but in all probability it does not mean that. If fact, as I have pointed out above, the yearly ratio of bitcoins lost is bound to converge toward zero very fast, which implies that the number of bitcoins still in circulation will remain above a large constant, say 10 million, FOREVER. That is why your problem will never be a problem.