I could see the appeal it could have, especially for people who like really small lenses. It would turn a MFT MILC into a pocket camera.
The thing is...there are two sort of pancake like normal zooms in the native format! This really blows my mind!
<p class="">at 0.9 inches<b>: Olympus 14-42mm EZ (for Electronic (only) zoom).</b>
<p class=""><b>~0.94 inches: </b><b>Panasonic LUMIX 12-32mm MEGA O.I.S. </b>
<p class=""><b>I apologize for inches, and not mm, and the little font change. I just happened to be trying to decide what would make the best low priced MILC pocket camera, and so, being a DSLR user, I had no idea that there were lenses that cover the entire "normal zoom range" with a less than an inch length form factor!</b>
<p class=""><b>Also, these are lowly kit lenses, and are not true pancakes, they are collapsible, they are not primes, not constant aperture, and as fast. </b>
<p class=""><b>...But I consider this to be kind of big news. MILC's are beginning to actually be tiny and sensible. In fact I've gotten to the point where I wish I owned one.</b>
<p class="">Your 28/2.8 fits right in. You need a normal zoom. You need a normal prime. They should, IMHO, not be the size of all outdoors. I really am starting to want a MFT camera! The only downside, is they are so small, I'd probably loose one!
It would complement the EF-M 22mm f2 STM on my EOS M quite nicely, making FF equivalents of 35mm f3.2 and 45mm f4.5.
It is tested on the M4/3rds Panasonic so we are getting a "sweet spot" sort of result.
It's the sort of lens that inspires, as you say, to a teeny weeny M4/3rds S/H body!