This question might be better answered by someone in the mobile industry, but I guess I'll ask it here since it does involve physics. I understand that wireless spectrum for mobile data is finite, and will run out at some point. Out of curiosity, what are the implications of that exactly? Does that mean that there's a hard physical limit on how fast future mobile networks can be, or how many subscribers they can support? Does that mean that there won't be '6G' or '7G' etc networks in the coming decades?