I sometimes wonder if the culture in Europe is different. I don't know a single person working in SWE who has an active GitHub presents or a personal blog. Of course, GitHub wasn't a thing during my college time (subversion was king, not sure if GitHub was available). But even now, of all the things you can do with your free time, why would you choose more coding or writing about coding? The people who are that passionate about coding have to be quite rare.

Personally, I tried to do side projects several times. But after a while I realized, that I really don't care and that it is not necessary for my employment. SWE is just a job, it's enjoyable work, but still nothing but work. I do enough at home to remain employable and to be decent at my job. There is no point doing any more.