What's the deal with MicroG?
I migrated to GrapheneOS in January and, although this sub helped me a lot, along with the Graphene help pages, I had some trouble with some apps, so I installed MicroG because, still unaware of sandboxing, I didn't want to activate Google Play Services (now I do).
I'm just a user that doesn't want to use Google anymore, but I'm trying to understand this exact process.
I get that MicroG intercepts calls that apps make to Google Play Services APIs, but how different and useful is it to have it, as opposed to just having Google Play Services sandboxed? Why do some apps block MicroG? Are push notifications and location the biggest dealbreakers here, or is there something in the big picture I'm missing? Or am I just misunderstanding everything? Does it even make sense to have both installed?
Sorry, I am truly lost about it.