[nitros]

The low base clock is likely RF certification related

[londons_explore]

Unlikely if the clock is entirely on-chip.

Clock signals on big motherboards are great RF radiators and hard to shield. But on a SoC, they aren't much of an issue.

[creshal]

RP2040 supports external crystal oscillators for precision applications and ships with one on the reference board, the internal ring oscillator is only recommended for low precision, low cost applications.