Given that, in order to maintain some structural integrity with all those holes, the shell is going to have to be thicker, any weight saving is going to be minimal. The saved weight will soon be replaced, as the mouse interior fills with detritus.
I hate the perforated lightweight mice too. Ugly as heck. Plus, I don't want a light mouse. I want a nice hefty mouse with a dang PINKY LIP and rough surface on the righthand side so I can lift it without squeezing. Do mice designers not use mice? How hard is it to add a nice lip on the right side so my pinky doesn't slide off. Why do I have to squeeze the stupid mouse so tight to lift it? C'mon guys. Do better. I want my thumb and pinky to have something to get UNDER so I can lift with zero effort. It's not that hard...
How many people actually use those highest settings though? Even 16,000 DPI seems pretty much unusable for just about anything, and is advertised more as a marketing gimmick that isn't necessarily going to be relevant to the actual tracking performance of a mouse sensor. Most competitive gamers use sensitivity in the 400 to 1,600 DPI range, so it tends to be pretty irrelevant whether one mouse supports up to 10 times that amount, and another supports up to 20 times. It's often possible to run a mouse at a high DPI and turn down sensitivity in each game's settings, but not all games offer good sensitivity adjustments, and it's questionable whether one will see much benefit from doing that.
Having a button set to the polling rate is pretty ridiculous though. Like whoever had the job of setting up the DPI select button misunderstood what they were supposed to be doing. Polling rate is not a setting you typically change after initially setting up a mouse. : P
In any case, I don't think I would trust the wireless capabilities of any gaming mouse to provide a reliable, low-latency experience unless it was independently tested to be close to a wired connection, like Logitech's recent "Lightspeed" mice. Some budget or productivity-focused wireless mice tend to have rather poor wireless latency.
Competitive gamers usually play at even below 1080p though. And when someone else plays a RTS at 4K, the (e)DPI requirement there may differ. And someone with an ultra-wide screen (or multi-screen setup) may even want to configure different DPI for horizontal and vertical mouse movements. At least from own experience, with a 27inch screen at 1440p, with 400 DPI I would have to move the wrist to get the cursor on desktop from one screen-edge to the other (without lifting the mouse), and with 800 DPI it is almost a full swipe - and that isn't great when moving the cursor around a lot e.g. in a game such as Cities: Skylines.
Which isn't to say that I am using 10,000 DPI myself. But there are a number of settings, such as the Windows pointer speed, some may want to lower and have higher DPI instead, and such as using e.g. 5,000 DPI as base for RTS, while having low in-game sensitivity for a shooter (which has such a setting). So I wouldn't say it is just a gimmick, even if it surely isn't that important to many an user.
But this mouse can do 16,000 DPI, upward of ten times the commonly-used sensitivity settings, so to claim that makes it "not up to par" with sensors that offer even higher DPI options is a bit questionable. These companies are advertising higher DPI numbers just for the sake of looking better on a spec sheet. Even on an extended desktop across a pair of 4K displays, DPI set that high would be quite unwieldy. When moving the mouse one inch moves the cursor 16,000 pixels, it's going to be difficult to click on anything accurately.
And while additional resolution might potentially improve mouse tracking slightly even at lower DPI settings, there's much more than just DPI that affects accuracy, and a sensor with higher DPI isn't necessarily going to be more accurate.