Will add my 2 cents here........
First, while I use a SLR for paying jobs I rent these days. For all personal shooting I've given up hauling big cameras, lenses, flashes etc. For two years now it's been a Canon G7X and now Mark II plus my iPhone 6s Plus.
The G1X III camera having an APS-C sensor in a G5X body is pretty amazing in my book. If you've held a G5X you know how small it is which means you might actually take it with you. Anything larger I just can't bear to haul and an iPhone (or Samsung) with even one App, Snapseed will make photos you'll be thrilled with.
As to the gripes about no 4K and a slow limited range lens......I don't own a 4K TV and that spec requires more data storage, etc. It's meaningless at least to me. The lens f-stops don't mean anything either as software can de-focus backgrounds, etc.
The weather proofing IS a big deal to me. Being an underwater photographer and dealer for Fantasea compact and Ikelite underwater housings means any camera to be used around water having seals is a huge plus.
Finally, the price.....While not wanting to be an early adopter paying top $$$$$ I weigh the benefit of getting a new easily transportable and usable tool versus the new images I'll be able to capture with it over years I keep equipment.
Believe I'm not awash in $$$$ but since going to rehab for GAS (Gear Acquisition Syndrome
many years ago having less has worked for me.....I'd rather maximize the capability of one tool and simply enjoy photography.
I'll bet many will buy this camera for the small size and larger sensor. Hopefully the 3X zoom lens and features delivers great photos and full reviews will tell.
To each his own!