But most alternatives choose not to retain personal data and have much more stringent privacy policies. Realistically I don't think the average individual can

But most alternatives choose not to retain personal data and have much more stringent privacy policies. Realistically I don't think the average individual can fathom how much personal data the likes of Google has on people. Small example, I deleted my entire Youtube subscription/history several times, I keep getting recommended the same things. Clearly there's more to 'deleting it entirely'.