If there’s one thing semantic web folks like it’s fragmentation
People always mention RDF when the semantic web comes up. It's really important to understand where W3C was in the early-2000s and that RDF was driven by those with an academic bent. No one working with microformats was interested in anything beyond the RDF basics because they were too impractical for use by web devs. Part of this was complexity (OWL, anyone?), but the main part was browser and tool support.
There's nothing wrong with RDF itself, the modern plain-text and JSON serializations are very simple and elegant. Even things like OWL are being reworked now with efforts like SHACL and ShEx (see e.g. https://arxiv.org/abs/2108.06096 for a description of how these relate to the more logical/formal, OWL-centered point of view).