This might be technically true, but is not true in any meaningful sense if another developer ever has to work with your code. They will have to deal with all your baggage, and their job will be much harder because of it.
... but I would still get advantages in terms of speed, maintainability, etc. from using a modern web development environment that I see no reason to give up. There are things like cache-busting hashes, linting, splitting js code in modules and using variables in SASS for things like colors, that to me are mandatory in a professional practice.
That's not the requirement I'm talking about. It's "multiple developers you don't know, of varying experience levels, will work on this project over the course of years".
They're going to clone the repository and have to make changes. Ignoring your stack is not an option. They have to figure it out, or throw it away and rebuild something else.
They'll be the ones paying the time cost of all the advantages you get by doing something complex but easy for you.
You may say this doesn't apply in your situation, and maybe right now it doesn't, but it almost always happens in any successful project eventually.
Why? Because I have a website template that solves many things for me, like:
- I see no reason not to use SASS or the latest ES even though I know how to. Or pug, for that matter... which I like. I also have a SASS template with some utilities and a particular code organization.
- Using an ES bundler allows you to throw in libraries from npm. I would not write the QR code myself, for instance.
- Automatically watches sources and recompiles.
- Adds hashes to asset filenames in order to cache-bust changes in CSS/JS/images (critical when using a CDN).
- Has placeholders for things I'll probably need, like the metadata for building previews in social networks.
- Is prepared for dealing with i18n, if the need arises.
- Future-proofing, since 80% of projects you think are small end up becoming larger. This is a single-page site, but if I wanted to publish this in Europe it'd already need two extra pages for the Privacy Policy + Impressum... so the single page site suddenly needs to worry about navigation.
- It's prepared for quickly deploying to AWS or Github Pages. It could be quickly tweaked for working on Cloudflare Pages or other hosting/CI environments that do the compilation for you.
And most importantly...
... my stack does not negatively affect the end result. All the extra baggage is just part of the development environment. If you want to skip my tools, they're quite easy to bypass and replace for any other transpiler... or you can just ignore my sources, reindent my compiled files and work on them directly.
PS: Back in the 90s I drew complex table layouts on graph paper, typed them down with vi, and ftped them to the hosting. I'm well aware of the alternatives. My current workflow + templates + helpers are based on the need to efficiently juggle A LOT of completely different projects every year as a freelance developer.