It's not literally half, but according to data for 2023, even around 35% of the world's population does not have access to the internet at all, while it is questionable how many people have a permanent and high-quality connection to the internet. Many members of this forum from some African countries have exactly this problem, their internet actually depends on whether they have electricity, and this makes their activities much more difficult - although this is not something specific only to Africa.

But even if we take the 2/3 who have access to the internet, looking at it as a whole, all researchers say that less than 5% of the world's population is in some way involved in cryptocurrencies, and of that number there are certainly many who have invested only in altcoins.

When you draw a line under all that information, then your question cannot get any kind of positive answer, regardless of which aspect of the problem you are talking about (if the problem exists at all).