Trust around WhatsApp / E2EE messaging apps

I am writing an academic paper (student), in a large part of it will be a discussion around the public's trust and reasoning into why they do / don't trust encrypted services such as WhatsApp, telegram etc...

I am planning to run a survey, but also I would like a source(s) to compare my results to, does anyone know of any sources around trust / public perception of WhatsApp etc... Even if not directly this but close enough this will …

apps e2ee messaging messaging apps privacy trust whatsapp