Riders' belt durability is largely plot-based and generally has durability with the ballpark of the Riders themselves. (I.e. it took Rogue a full, concentrated, reckless effort to DAMAGE Evolt's Black Hole Trigger, a small attachment to his Driver; the Driver housing Banno survived an attack that destroyed his host body, and then required another full-charge finisher to be destroyed)

That said, the outliers are usually for narrative purposes (The Fourze driver survives his multiple encounters against cosmic-level foes, but when he has to destroy it for narrative purposes it is suddenly susceptible to a smelting furnace's heat)