I do https://wordsandbuttons.online/ as a personal-ish website. I don't append my face to every page but a visitor is usually a few clicks away from my other works so the site is de-facto more or less personal.

First of all, it's a nice hobby. No bullshit programming, no frameworks, no dependencies, no annoying editors. I just write my code and text and enjoy doing so.

Second, it gives powerful motivation to study. I'm now writing a new page on rational interpolation and just yesterday I accidentally found a very simple way to avoid the Runge effect. I was just playing with interactives and it came out of the blue. There is no way I would have learned it otherwise.

Third, it helped me cement a publishing deal with Manning. They came to me and proposed to propose them a book on geometry. And so I did. The book is called Geometry for Programmers and it's coming this summer.

Fourth, I do public lectures (or at least I used to before the war), and the audience loves interactive illustrations. So I usually turn my site pages into presentation-like pages and do lectures with them.

So for me, having a website pays off in multiple ways.