Years ago there was a surge of people putting out blogs and websites like that which brought demand for plug-ins, etc. Long form text content isn't the trend now, its podcasts and vlogs, etc. In some ways, amateur content creators just need a smartphone.
I think if someone was going to build a platform for nearly anyone to publish content it would need to have easy plugins to do things with video and audio and not be focused just on text. Allowing people to build plug-ins and themes and install them is a key feature.
I think the technology choice that would make this easiest these days is JavaScript (even tho I'm not a user). The numbers of people out there today with deep JS skills are similar to when there were a lot of PHP developers building WordPress plugins. It allows for front and back end development which could be an advantage to a plugin based tool like WordPress is.
Yes, because it's still the best tool for certain tasks. A blog with well integrated commenting, for example.
If I were building it today, I would write it in golang and I would offer the ability to export static sites. I would make comments an optional or external module since spam has largely ruined comments sections for anyone who doesn't get many legitimate comments. Why golang? Because it typically has the easiest deploy story, IMO.
If I were writing it then, I would have written it in Python and chosen PostgreSQL as the database. Of course, back then that is what I would have chosen as well.