Such "rubber" zoom lenses never come w/o strong distortion, either on short or long focal lengths (most probably at the wide angle end). I think all manufacturers of such extreme wide angle to tele zooms rely on a heavy-sided in-camera correction of all sorts of distortion, vignetting, and aberrations to keep weight, size, and price within tolerable limits. Personally, I therefore prefer dedicated tele or wide angle zooms (if not primes anyway) with much more properly designed optics. Even Canon's new long RF 200-800 mm zoom was surely much easier to design with quite well-corrected optical aberrations - vignetting seems to be a bit pronounced but that's not a real issue.
Btw I still wait for my RF 200-800...
Germany and/or Europe seems to be much less attractive for Japanese camera makers than it still was a decade ago, so we are the last ones to get new lenses - okay, people living in Tierra del Fuego may have to be even more patient, I guess.