Is Mercedes in Decline? Jane won’t like us saying this—we don’t know exactly what she does—but protecting the Mercedes brand from media barbarians like us seems to be on her to-do list. That said, let’s dig in.

YouTuber Car Care Nut, an engineer, has built a niche following by reviewing cars the way an engineer would: inspecting engine bays, lifting cars to check the chassis, and pointing out design flaws. His takeaway? Mercedes’ engineering quality is slipping.

Where once metal parts were the standard, plastic is now everywhere. And anyone who’s dealt with plastic knows it becomes brittle, cracks, and eventually fails. In a car, where parts heat up, expand, and contract with the cold, plastic just doesn’t hold up.

The new Mercedes W223 uses more plastic than ever—both under the hood and in chassis components. That likely means higher failure rates down the line. We don’t have full reliability stats yet, but don’t be surprised if issues start popping up.

The interior tells a similar story. Once the gold standard, the S-Class now shows a clear decline in quality. While this may have started as early as the W221, the latest models make it impossible to ignore.

It feels like a line has been crossed. If the S-Class is being targeted for cost-cutting, it suggests Mercedes is either under financial pressure or prioritizing shareholder profits over engineering excellence.

And here’s the bottom line: if the S-Class stops being the benchmark, Mercedes risks losing the prestige and reputation it has spent decades building. At that point, the company will only have itself to blame.