Except for the digital communication, inductance mostly helps you here, not hurts. You don't want submicrosecond rise times on your power rails. I haven't see

Except for the digital communication, inductance mostly helps you here, not hurts. You don't want submicrosecond rise times on your power rails. I haven't seen modern SoCs with tightly integrated PMICs like you're describing, but they could certainly exist. But if they're not using an off-the-shelf chip, why don't they just integrate their power management functions into the SoC? Not enough balls?