There are what I would call "good oldie" MOOCs that people frequently recommend, like algorithms on coursera. Most of them are from 2012-2013.
Now will be some rant and justification for the question, the question itself is in the last paragraph.
At the time (2012-2013) I was very hyped and enthusiastic, imagining new courses of the same quality and kind will be appearing at the same rate in future. By kind I mean university level subjects, fundamental topics that have high return of investment.
But it seems to me it went quite differently. I don't really see any new courses being published and recommended on the lists among good oldies. My own experience with stuff that came later also wasn't as pleasant, I started dropping courses much more often.
The platforms themselves changed significantly:
1. Switch from fundamental to hands-on subjects like technologies and frameworks.
2. Switching to paid model (not that I have anything against it, although being poor in a poor country I avoid paying as much as I can and haven't paid for a single certificate). This leads to less people checking out the course and giving it a "media coverage".
3. Switching from strict start-end date to "take anytime you want". Because of that the social element for me has been essentially lost, the forums are half-dead.
4. Increased amount of courses. Together with (1) this makes it hard to find something by random exploration. When I open edx computer science section I have to go through pages and pages of microsoft courses about their technologies.
This made me gradually lose interest in MOOCs and switch to books and self-learning. I occasionally go back to MOOC platforms or MOOC aggregators, thinking maybe I just missed something or something interesting came out recently.
Did you take any good (valuable, mind-expanding, long-term rewarding, intellectually stimulating) courses that aren't famous and have a high chance of being overlooked?