Timing chains are one of those things, much like tires and brakes, where the car just needs it when it needs it. You can complain about little use you got out of it, and I feel your pain (been there before), but there's still no way around it.

I have a 1985 380SE with the same motor, and everybody has always said to do the chain every 50k (or less). Have you ever seen the chain out of the car? If you uncoupled it, it would probably be 8' long. The design was ridiculously complex and lengthy, and the double-row chain was really only a bandaid for this. Even the double-row chains don't last long, they really just help with preventing catastrophic failure, but their lifespan still isn't great compared with any other motor. These really do eat chains.

It's the one real weakness in an otherwise bulletproof motor, so I think we're still doing ok overall with the 380s. One throttle body or a wiring harness or an ADS shock on my M120 R129 would cost as much as two or three timing chain replacements on the 380se. Lol. It can always be worse.