The problem isn't limited to people learning frameworks instead of languages; I work with developers who don't know the network stack at all - no concept (beyond the bare basics) of how their code gets from a server to a browser and the steps between and the related technology. When I ask things like "does the server support HTTP/2 or /3" or "can you setup a local certificate so we can use https for localhost" I almost invariable get blank stares (or long pauses on Teams/Slack) and a question in reply: "Where do I look for that?"