Running it at very high RPM's for extended periods will definitely cause the engine to wear out sooner. Cars in Germany that are constantly driven hard on the autobahn do not last as long as the same car driven at more moderate speeds.
That said, my Euro 240D, with no tach seems to run a zillion RPM at 70 or 80. But I drove the original engine to 380,000 miles before overhaul. more than 90% of those miles were screaming down the highway. I changed oil regularly and took care of it, but drove the heck out of it. After all in a 240D you only have two throttle settings; foot not touching the throttle, and foot holding the throttle to the floor. That's the only way you can get anywhere in one.
Drive it and enjoy,