Late 2025 I made a decision: instead of chasing every emerging-tech opinion piece, I would actually pick four skills the internet was hyping and spend exactly six months on each. Real practice. Real projects. Real interviews where I claimed the skill. Then I would compare the resulting interview yield, project value, and time-to-first-job-impact against each other and against the original loud claims. Two years later I have the data. One skill earned its hype. Three did not. This post is the comparison — and the lesson is not which skill, but what makes a skill worth learning in 2026 . The four skills I picked them from the top of the "must-learn" lists I was reading at the start of 2024: Rust — system-language hype, "everyone is rewriting in Rust" Kubernetes — "every senior engineer needs to know K8s" AI/LLM application engineering — "wrapping LLMs is the new web framework" Data engineering / dbt + warehouse stack — "data is the new oil and someone has to plumb it" Each got six months.…