Unlike petrol, diesel use glow plug when the car needs to be start, the older the car goes, the glow plug performance dropped to some extend, diesel will required multiple rounds of glow plug heat up. The battery are constantly discharged over this process and if the battery is not being proper charge up (i.e. short trips/traffic jam), the lifespan of the battery is going to below. Hence, i believe that is one of the reason why battery for diesel is having lower warranty period.
Beside electronics that consume power, we need to consider the design of engine bay.. a lot of the modern car put everything everything close to each other in engine bay to give more space in cabin. The trapped heat is bad for the battery. Having an isolation box to move battery from the engine bay certainly is going to be a good idea to prolong the lifespan.
Battery brand that has lasted 4 years or more.