ve3jlg GrapheneOS does not bundle any type of Google service or app in it. If someone is not okay with using Sandboxed Google Play after fully understanding how it works and that it is fundamentally different compared to privileged play services that you would find on the Stock OS, they can simply choose to not use it.
Not everyone's threat model, needs, or expectations are the same. People need the apps they depend on to work. The best way for them to do that is to use Sandboxed Google Play. It is better than using Stock OS with privileged play services, and it is much better, and much more secure than other approaches trying to do the same thing.
If you can use all the apps you need without Sandboxed Google Play, you're free to not use it; in fact, that would be ideal, but people's journey into privacy doesn't happen instantly, and the more you try to change at once, the more likely you are to completely give up and go back to something objectively worse.
People who use Sandboxed Google Play on GrapheneOS are already miles ahead of most people when it comes to their phones.