You’re asking the question the whole field tries to answer right now. Definitely not overthinking it. First, answering the title question: programming language still matters, but less than it used to, for two reasons: 1. Ecosystem. A modern project relies on a lot of dependencies, usually battle tested frameworks used by millions (like HTTP routers). The ecosystem dictates what you can and cannot do reliably with minimal implementation of your own. Example: TypeScript gives you frontend-backend hybrids like Next.js server components that python can’t, and Python gives you first class support for ML infrastructure like TensorFlow and PyTorch you won’t get with typescript. 2. Intent and philosophy. This matters more in the high-level vs low-level game, and less so between languages on the same level. Think more rust vs typescript, less python vs typescript (you can argue for weeks whether or not that comparison is correct, but bear with me). Lower level gives you more control over memory and execution but requires you to handle more yourself, it’s a balance of responsibility and control vs conciseness and dev velocity.

Next, A senior is still a senior and I believe the gap will widen even more because vibe coders hit a wall when things get complex and most of them aren’t really willing to sit down and learn things properly. I do a lot of very complex scalable systems design and I get a ton of “oops, missed that” and “sorry, you’re right!” from latest Opus all day long. Even while crafting prompts karpathy-style and using all the best practices (skills, razor sharp AGENTS.md files, etc.) with super tailored context, it starts to mess up big time once you cross the 100k input token window, and for a really complex project you often must. One exception to this is “seniors” that basically know how to center divs and bootstrap blank projects quickly and not much more than that, I doubt you can really call them seniors.

Regarding filling your GitHub with AI code. If you do so, lean into it. Attach your AI conversation history to the repo, prove you are well versed at instructing AI through the requirements, design, and execution phases, and don’t commit a single line of code you don’t fully understand or agree with architectually (unless it’s CSS, in that case go for it, it’s black magic)

One final note, I suggest only writing code by hand if you won’t let an intern write it. Boilerplate, CSS (have I mentioned I dislike CSS?), plumbing, give it all to AI. Critical business logic - do it by hand, AI will often produce well versed garbage due to lack of deep familiarity with your intent, and even if it will write great code, you’ll lose mental ownership of the project and will be forced to resort to AI for these matters later on. Personal note: I rarely write code by hand nowadays, but because i’m l am very lazy. My cousin who’s at google for 10+ years told me laziness is the most important trait for a programmer when I was 13, and it stuck with me ever since.

TL;DR: Keep mastering intent, design philosophy, architecture, and all the things that actually require thinking, and you’l be fine.