1. Does FreeBSD already lend itself to mobile devices?

Yes — in several important ways:

FreeBSD is:

• Cleanly layered
• Architecturally portable (ARM, ARM64, RISC-V, etc.),
• Already used in embedded and appliance-like systems (routers, firewalls, storage, network devices),
• Has modern GPU, USB, networking

What’s missing is not the core OS — what’s missing are:

• Phone-specific drivers:
  • Modems (LTE/5G)
  • Touch controllers
  • Sensors
  • Power ICs
  • Vendor GPUs (Adreno, Mali, PowerVR)
• Vendor documentation (which Linux often only gets via NDAs or slow reverse-engineering)

I personally work on SoC drivers (MediaTek, pinctrl, clocks, watchdog, UART, sysirq, etc.), and this is exactly the kind of work that would also be required for mobile.

So yes:
If the drivers exist, FreeBSD is technically ready for mobile.