Hi Raphaël! I think this is a very interesting idea. I checked the app but it seems to be down at the moment. After rebooting it it threw some error codes on the main page. Are you still working on this, or have you perhaps found an alternative? I came across your post as I am searching for some helpful resources to determine 'neglectedness' of different fields/problems.
This is a link to https://share.streamlit.io/omniscienceacademy/playground_fieldsofstudy/main/app.py
We (the omniscience.academy team) have used the MAG data to create some cool visualizations, allowing you to see/explore the number of articles in each field/subfield of study.
This is a draft application, feedback is most welcome.
We hope this app could help assess the degree of neglectedness of each field of study.
This is awesome. Would love to hear some examples of how you think it can be used