This problem has to do with the text rendering engine. I believe that if Affinity were to adopt Apple's default text rendering engine, then the problem of using Unicode fonts with non-Latin scripts would go away entirely.
Note that native Apple apps do not have this problem - Hindi-language text works perfectly with Pages, Numbers, Keynote, Safari, etc. It also works across Microsoft's suite of applications. It's clunkier with Adobe's suite but it does work with InDesign and Photoshop once you have things properly set up. Even Pixelmator, which uses Apple's default text rendering engines, fully supports Hindi-language text.
For Affinity, doing a complete transplant from an Affinity-created engine to Apple's default engine might be a heavy lift, but maybe there is a way to add a user preference or to add multiple text rendering options? Please at least look into it and come up with some strategy or roadmap...
This problem has to do with the text rendering engine. I believe that if Affinity were to adopt Apple's default text rendering engine, then the problem of using Unicode fonts with non-Latin scripts would go away entirely.
Note that native Apple apps do not have this problem - Hindi-language text works perfectly with Pages, Numbers, Keynote, Safari, etc. It also works across Microsoft's suite of applications. It's clunkier with Adobe's suite but it does work with InDesign and Photoshop once you have things properly set up. Even Pixelmator, which uses Apple's default text rendering engines, fully supports Hindi-language text.
For Affinity, doing a complete transplant from an Affinity-created engine to Apple's default engine might be a heavy lift, but maybe there is a way to add a user preference or to add multiple text rendering options? Please at least look into it and come up with some strategy or roadmap...