Twine is supported by a nonprofit:
The Interactive Fiction Technology Foundation (IFTF) helps ensure the ongoing maintenance, improvement, and preservation of the tools and services crucial to the creation and distribution of interactive fiction, as well as the development of new projects to foster the continued growth of this art form.
The web site says
Twine’s diverse userbase includes Hollywood studios, schools, and disadvantaged creative communities.
I would love to know more about school use!
I also saw this on the web site and found it interesting:
Interactive fiction has always been an accessible medium. IF stories are primarily text-based and tend to unfold at a pace set by the player. Therefore, IF presents significantly fewer barriers for players with disabilities than most other kinds of video games. However, as IF creation and play technologies advance in new directions, accessibility doesn’t always receive the attention that it deserves.
In late 2016, IFTF launched a project to test IF software for adherence to best practices in user accessibility. The Accessibility Testing Committee ran a test program for popular IF tools and games, and reported its findings, along with a list of accessibility-improving recommendations, in mid-2019. (The program ended, as intended from the start, with that report’s delivery.)