The phone app on Android should be high availability. It should never crash, it should take priority over anything else. Everything else is secondary. Facebook, twitter, and yes, Bixby.
Whether it’s a cell phone or a smart phone, it has the word phone in it. It must function.
One of the claims to fame of Blackberry was that the OS was solid. In fact, they were so into solidness that they acquired QNX, makers of high availability and realtime version of Linux. This eventually made its way into versions of their phone.
While Samsung is doing some cool things on the phone side, in particular the new ability to send stickers to other Samsung device users during calls or enabling WiFi and HD calling (VoLTE), the app itself must never crash.