> What is "its alternative"?

I meant alternativeS, sorry. Well, anything AOSP-based that is not Android.

> The manufacturers aren't blocking the installing of GrapheneOS...

Of course they are not. But they produce hardware that is not secure enough for GrapheneOS to consider. I wish they saw value in GrapheneOS and produced hardware that met their requirements.

It's actually weird, because I'm convinced that it's completely worth it: just add those requirements to the design of one new model, and a potential of hundreds of thousands of people may buy it just for GrapheneOS.