I'm not sure I'd call our current geopolitical status stable in any way. Multiple major wars, historic superpowers losing their absolute minds, fascism rising, even discontent in the EU.

This is an artifact of the instability of our current times. USD reserves are falling because the US is no longer a stable country offering a stable currency. Plus we keep demanding more tarriffs in effect reducing the real value of a US dollar.

Stability would appear as more confidence in USD, not less.