For now everything is pure speculation, but the fact remains the Z4 could be in trouble.
Fact: premium roadster sales have been dwindling in recent times, as both the BMW Z4 and Mercedes-Benz SLK have experienced a nosedive in sales despite being solid cars. Not surprisingly, Zee Germans aren’t too thrilled. So it now begs the question whether either one will spawn a successor when the time comes. BMW boss Norbert Reithofer recently stated the possibility of a Z4 successor in a recent interview, but "it could be part of a new sports car architecture." So what’s he referring to?
Perhaps the joint sports car venture between BMW and Toyota. However, BMW Blog is claiming a Z4 successor is unlikely because it could be replaced by the long-rumored Z2. That latter would be much more compact and more in line size wise with the old Z3. Rear-wheel-drive could also be in question simply because the Z4 shares a lot of its architecture with the previous-gen 3 Series. With that car’s replacement bigger than ever before, it makes no sense for BMW to continue building the Z4 on a now dated platform and it certainly can’t get any bigger than it already is. The solution could be a new front-wheel-drive platform currently in development.