Lexus vs Mercedes-Benz: Who Copied Whom?

Looking at M-B vs Lexus cars, they look very similar-in fact it is hard to tell the C_series M-B models from Lexus. My question: did Lexus copy M-B. or was it the other way around? Seems to me that Lexus is a better car (reliability-wise), is M-B losing ground to them?

Toyota owns the DMV in Japan. All cars must be submitted to the DMV before they can be driven in Japan. Several years before.

Mercedes designs cars on a seven year cycle. Toyota’s cycle is shorter, on the neighborhood of four years.