I don't think the post implied that this package writing activity was a write-only activity where reading and learning is strictly forbidden.
> You can find open source licensed packages, read them to understand them, and then copy them into your config. Doing everything from scratch is a waste of time unless you enjoy the process (in which case go nuts).
The post clearly indicates the relatively large set of open source packages they looked at and understood before doing their own packages. The author graciously acknowledges them and their influence on the work:
"Emacs Solo doesn't install external packages, it is deeply influenced by them. diff-hl, ace-window, olivetti, doom-modeline, exec-path-from-shell, eldoc-box, rainbow-delimiters, sudo-edit, and many others showed me what was possible and set the bar for what a good Emacs experience looks like. Where specific credit is due, it's noted in the source code itself."
I think of it more like building stuff out of Lego without following any instructions.
It seems pretty clear that the "why" is "because it's there"
Sounds good enough for me
> It's roughly equivalent to trying to discover all of our scientific knowledge yourself from scratch vs taking "for granted" the knowledge discovered by your forebears.
The author do have another config with all the bells and whistles. But Emacs does come with a lot of packages and tweaking them isn't that much work compared to building a full suite like Helm, especially with the awesome documentation system. Getting a v0.x of anything can be a matter of minutes. And then you wake up one day and you've built a whole OS for your workflows.