The biggest problem to remember is, once again, criminalizing privacy protection tools that citizens can use for free, when laws exist to require companies to protect their customers' data. It's an aberration, It discredits concerned individuals who use these tools, it scares off people who might have been interested in them, and it reinforces people's preconceived notions that those who seek to protect their data have something shady to hide.
In addition to security and privacy, one point that is probably underestimated is really that feeling of owning the device and having greater peace of mind when using it, no incessant notifications from services you don't want, no advice to display or activate this or that, no AI, just the relationship between me and the phone, what I decide to do with it, and the useful security/privacy features it offers me.