You make the typical mistake of looking at current problems and failing to envision solutions. Like people considered early 19th century automobiles ("This will never work! These machines are too noisy. They keep breaking. Roads are not smooth enough. There are no convenient gas stations.").

Humans are good at finding solutions to technical problems. It was already demonstrated a quad core CPU and 8Mbit/s of bandwidth are already sufficient to support scaling to at least 2000 tps. The problem is people don't agree how to allow this to happen (Lightning network, or block size increase, etc). But that too will eventually be resolved :)