Trivial answer is Google Docs and equivalents. Etherpad is one such equivalent that has some advantages in respecting privacy and self-hosting. Seems likely you've considered cloud-based office software and found it lacking, though.
Personal knowledge management software like Roam, Obsidian, Logseq, etc., is generally trying to offer this level of generality. Many of these variants store data in simple data types, allow several different structures (markup languages, tables with formulas, nested lists, embedding of quick drawings, and so on, with OneNote as one of the most flexible on this point), and strong searching and crosslinking. Automation is less well-supported, both in running scripts internally and in interfacing with an API. Collaboration is very poorly supported, but this is a significant development area and several of the major contenders are competing to release it first.
However, the gold standard in general purpose computing has got to be emacs. The only one of these things that emacs org-mode is bad at is real time collaboration. If you want collaboration in emacs you probably can't make it much faster than pushing and pulling git commits. For everything else, storing your contents in a git repo and accessing them with emacs is highly effective. The downside is that maintaining your emacs configuration in a usable state is difficult and requires significant expertise. Packages and distributions change rapidly and often break each other, so you need to be good at troubleshooting and keep up on the development news. Using a good distro like Doom Emacs or Spacemacs makes things easier, but definitely doesn't solve the problems. Not to mention the learning curve, which isn't trivial. It isn't worth it for most people, but it's certainly the closest you can get to a fully general computing system using modern software.
Trivial answer is Google Docs and equivalents. Etherpad is one such equivalent that has some advantages in respecting privacy and self-hosting. Seems likely you've considered cloud-based office software and found it lacking, though.
Personal knowledge management software like Roam, Obsidian, Logseq, etc., is generally trying to offer this level of generality. Many of these variants store data in simple data types, allow several different structures (markup languages, tables with formulas, nested lists, embedding of quick drawings, and so on, with OneNote as one of the most flexible on this point), and strong searching and crosslinking. Automation is less well-supported, both in running scripts internally and in interfacing with an API. Collaboration is very poorly supported, but this is a significant development area and several of the major contenders are competing to release it first.
However, the gold standard in general purpose computing has got to be emacs. The only one of these things that emacs org-mode is bad at is real time collaboration. If you want collaboration in emacs you probably can't make it much faster than pushing and pulling git commits. For everything else, storing your contents in a git repo and accessing them with emacs is highly effective. The downside is that maintaining your emacs configuration in a usable state is difficult and requires significant expertise. Packages and distributions change rapidly and often break each other, so you need to be good at troubleshooting and keep up on the development news. Using a good distro like Doom Emacs or Spacemacs makes things easier, but definitely doesn't solve the problems. Not to mention the learning curve, which isn't trivial. It isn't worth it for most people, but it's certainly the closest you can get to a fully general computing system using modern software.