You essentially describe the motivation for Stiftung Warentest [0]. They’re massively successful in Germany, and I rely on their tests for many consumer goods I buy. Access isn’t free though, typically costs around 5EUR per test. Coincidentally, they recently tested sunscreen [1].

[0] https://en.m.wikipedia.org/wiki/Stiftung_Warentest

[1] https://www.test.de/Test-Sonnencreme-und-Sonnenspray-fuer-Er...