This is one of multiple carrier apps in the stock Pixel OS which we don't include in GrapheneOS. We were aware of it already since we had to go through them and figure out why they exist. We could embrace this fearmongering and leverage it for marketing, but we aren't dishonest.
Discussion
"iVerify vice president of research [...] points out that while Showcase represents a concerning exposure for Pixel devices, it is turned off by default. This means that an attacker would first need to turn the application on in a target's device before being able to exploit it."