I have no clue if its "worth it". I've been writing forever and can't stop writing (
https://jonpauluritis.com). Similarly, I've been reading forever and can't stop... this year I resolved to try and read less, and I think I've already read ~10 books.
To answer your other questions:
*Did it help to get noticed/ find jobs or other opportunities?*
YES. This however is not linear. No one has ever been like, "would you like to interview" because they read something I wrote. People just remember you more or you have more reasons to interact with them. You impress them more at work because you can communicate more effectively which is like 30% or 40% of the job. (my code is more readable too)
*Do you learn something new from it?*
Sure, but again there's a lot learned that doesn't fit nicely into a box of skills. I'll give you an example....
Neil Strauss has a 3 edit process for writing, something like: write for yourself, edit your piece so that it's useful, edit your piece so that the haters don't have any material. This generalizes to all sorts of things. You could use that same sort of logic for a first date. Go out on a date for yourself first, make sure that the other person enjoys it, make sure that you aren't setting yourself up for failure with anyone who would comment about the date.
I think you learn a lot by writing but there's really no way to tell if it will be useful to you.
*Self hosted is too much maintenance...*
Yes, but this has gotten MASSIVELY better with cloudflare pages, Netlify, etc. My trick here is to simplify then iterate. Start with just the base theme... don't do anything to it... just write. With cloudflare pages you just `git commit -am 'message' && git push origin master` and it's published. I'm not a big fan of the medium/blogger scene - it's a personal preference.
*Writing up my thoughts in presentable state took too much time/effort*
I have a couple of tricks for this... first, go SMALL. very SMALL. 400 words is fast to write and fast to edit. 400 words is about what it takes for a short story, or a well thought out idea. You'll probably bleed into 500 words if you aim for 400 but it will keep you from writing those 2000 word monsters that suck up weekends. BUT it will also lead to the style of writing that will have you put out 1200 word pieces quickly. Next, stop caring what people thing, just publish it. Jack Conte has a beautiful speech on this (https://youtu.be/LzwwMGxohnI). Lastly, I'm lazy so I use tools to help me edit. Grammarly works great, but theres some open source cli packages if you work in plain text or markdown.