Thank you all for the many great answers! Definitely a lot to look at! Currently Appsmith (and/or) Lowdefy seem to fit best for me.

In case you're interested, these are all the products/resources given so far:

http://superset.apache.org

https://adsharma.github.io/flattools-programs/

https://adsharma.github.io/fquery/

https://apex.oracle.com

https://app.spanrr.com

https://arctype.com

https://baserow.io

https://bubble.io

https://deepnote.com

https://directus.io

https://django-sql-explorer.readthedocs.io

https://doc.seekwell.io

https://docs.djangoproject.com/en/3.1/intro/tutorial02

https://first-django-admin.readthedocs.io/

https://frappeframework.com

https://getzenbase.com

https://github.com/appsmithorg/appsmith

https://github.com/directus/directus

https://github.com/marmelab/react-admin

https://github.com/metabase/metabase

https://github.com/netlify/netlify-cms

https://github.com/oxan/djangorestframework-dataclasses

https://github.com/priyank-purohit/PostGUI

https://github.com/shannah/xataface

https://github.com/skorokithakis/django-project-template

https://github.com/strapi/strapi

https://hypermachine.substack.com

https://lowdefy.com

https://metacpan.org/pod/CGI::FormBuilder

https://ninox.com/de

https://powerapps.microsoft.com

https://retool.com

https://saltcorn.com

https://seekwell.io

https://solutions.appsheet.com/how-to-create-an-app

https://stackerhq.com

https://subzero.cloud/

https://tableplus.com/

https://voyager.devdojo.com/

https://www.appsmith.com/

https://www.basedash.com

https://www.datatrucker.io/

https://www.forestadmin.com

https://www.glideapps.com/

https://www.noodl.net/

https://www.nubuilder.com/

https://www.stackerhq.com/

https://nocode.tech