When I was a student I always took notes with a fountain pen, and I was the only one in the class who could log pretty much everything that was said, and with relatively good handwriting for the speed. A lot of people photocopied my notes!
Maintenance depends on the pen. Some require frequent cleaning, but for example, I have a Platinum Century #3776 that can sit unused for a month and will still write perfectly with no fuss (it has a sealing mechanism that prevents the ink from drying). I use it with Platinum's blue-black ink, which is one of the mythical iron gall inks, but since the nib is gold and the pen is designed so that no other metal parts are in contact with the ink, it's not going to eat my pen any time soon. I think you could give that pen+cartridges combination to anyone and it will probably run for years without maintenance (although I do clean it every few months just in case).
From this list, I can personally vouch for the Platinum Preppy and Pilot Metropolitan. Though the Preppy is a disposable, the catridges from the non-disposable Platinum pens fit it. You could could even get an eyedropper and refill the cartridge from a bottle of ink.
https://www.jetpens.com/blog/great-beginner-fountain-pens-th...
Most of my collection is in the under $20 range, most under $2.50 and the worst I've had is the ink had dried, which took some soaking in water for a bit to get out, but this was from letting a pen sit unused for months.
I have a Pilot Metropolitan and it dries pretty fast.
I have heard that some Sailor pens also have a similar sealing mechanism, but I don't really know which. I have tried maybe a dozen fountain pens a bunch of inks, but I'm far from being an expert. However, if you go to the forums at http://www.fountainpennetwork.com/forum/ you will find real experts. You can ask for what you need and you will get answers for sure, it's an awesome community.
To re-frame your analogy to suit a more HN centric view: Why would most developers bother with the hassle and maintenance of Linux when they could just slap Windows 10 on a PC and code away in an IDE easily?
In any case, I love my fountain pen. Not expensive, just a Pilot Metropolitan. I don't have the hand stamina that I did back when I had to handwrite practically everything, so I really appreciate the effortless experience of using a fountain pen.
I think gel pens are more practical tools, but I like the image better as well. To me, fountain pens are like fedoras... people think wearing a fedora makes you classy like some noir detective. Except to everyone else, it makes you look sily.