Id sooner have the wet belt - in the Fester its easy to eyeball the belt at the top pulley through thenfiller assess its condition, so you've plenty of warning should any driver be bothered to look. There is even a tool you can insert to measure the belt and check for any telltale swelling.
Conversely, timing chains are in sealed chests and until it makes a noise (or, even worse, the engine stops making any noise!) you cant check them without major disassembly.
Even worse, many timing chain motors (BMW are fond of this) aren't designed to be replaced and require the engine be removed to swap out the chain, which is spendy.
When a cam train fails it doesn't matter what it made from - you're up sheet creek.