This is the same for any crypto coin. Certainly not unique to Gridcoin.
Ethereum tried to be many things mostly a decentral computer. Turned out to be a super expensive decentral computer and that it isn't really so decentral in the current version. However its technically used this way by some people so that de-facto means it has a valid use case. It can hardly compete against newer similar projects but thats another story.
BCH solves nothing, the larger block size may allows some more Tx but you still have 10min block times and then wait for however many confirmation blocks you want. Not exactly how I imagine p2p cash is supposed to work. and if the throughput would reach the new max with the new block size it would suffer exploding fees just like the "main" bitcoin. It does not scale better it just has a higher limit not one that would allow any meaningful throughput to use it as a global p2p cash system. no one has it to use it as p2p cash. Everyone has it to sell it for profit later on.