You are probably right on the engineers ignoring sound for other spec improvements. But I do not think that is a wise optimization. At this point, most ~20V Li-Ion battery powered drills have been cheap, powerful, and have high battery life. Tweaking for a bit more at the expense of sound when you make the tool almost unusable in some modes (hammer drill) makes little sense. As I was mentioning they can be so loud that it is problematic even with extreme ear protection. Using something like that without ear protection will quickly give you permanent hearing damage.
To me, the main issues with battery powered drills these days are ergonomics (want light and compact), sound, and rpms. Most have more than enough torque and good battery life if used with undamaged cells. rpms in drill modes for small drills is another issue. Only a very few will reach high rpms (I think they limit to get good battery life and optimize low rpm torque). So they are typically too slow for rapid drilling with bits less than ~1/8" diameter. For such small holes, I typically use hex chuck impact drivers (get a lot of rpm with good enough speed control and typically will not hammer for small bits) using small drill bits with hex shanks. Short bits with hex shanks work best to limit breakage. I use hex chuck impact drivers a LOT for pre-drilling for screws and rapidly swapping out the drive bit for the screw. I save the battery drill for making larger holes OR when I need hammer drilling (which I avoid due to the sound issue and I use my SDS corded drill which hammers much better anyway: so it only gets used for one off holes I want to drill quickly with minimal setup ... which necessitates finding ear protection due to the sound so it does not save much relative to running a cord). If I could find a battery drill in my battery line (DeWalt) that was light, compact, capable of higher speed in some ranges, and not so damn loud, and had a metal keyless chuck, then I would be all in. I do not care so much if the battery lasts super long: I use battery drills with small batteries since I only generally drill limited numbers of large holes at any one time and prefer the drill to be light. Too much noise is a major factor for the hammer drilling mode. My present DeWalt battery drill is very loud (though probably not hearing damage threshold) even without hammering.
Dewalt still offers a cordless drill with a three speed gear box, with 2000rpm rotation.
(I have no clue about noise).
(If I recall correctly, Dewalt, or maybe Hilti were the first to offer an gear for higher speed in a cordless drill).
Complete tough drilling applications with the 20V MAX* XR® brushless cordless 3-speed hammer drill/driver. Featuring a heavy-duty ratcheting nitro-carburized metal chuck with carbide inserts for superior bit gripping strength and a high-efficiency brushless motor, this tool delivers impressive...
www.dewalt.com
Fein makes a cordless drill with a four speed gear box with 430/850/2000/4000rpm rotational speeds.
But with the Fein you would need to buy into the AmpShare system.
Festool also offers a four speed drill, but again, different battery system.
Hilti offers a four speed drill as well, but the top speed is around 2200 rpms.
All of these drills either come with, or can use an all steel chuck.
Of course the negative with the non-Dewalt drills would be battery systems.
Fein supposedly actually makes their tools for industrial users, so they include sound and vibration information.
Dewalt and Hilti don’t list sounds specs, at least on their US sites, although maybe if you can find the equivalent models on Euro sites the information would be listed.