Thinking about it, some of the "excessive" depth requirement might be due to the desire to keep from inducing eddy currents in things in a drawer beneath an making them unexpectedly hot.

Usually those 'requirements' are for air circulation. IIRC, the Electolux vents from the top edge and hence does not require much clearance below it. Another solution is to provide air vents behind and/or along the sides of the cabinet.

if you search for "thermador induction" , there is a thread where someone mounted the heat shield in the top drawer and that allowed almost full use of the top drawer.

I recently installed a GE Profile induction 30" unit (PHP900)and I love it. I researched the issue of clearance pretty obsessively and exchanged emails with GE as well as some other folks. My take on it is that the main reason it needs an insane amount of clearance is due to the electronics beneath. They can't heat up too much. I had my main silverware drawer under the cook top and I really had no other space to relocate these items. My eventual compromise was to have the drawer made more shallow. Previously the silverware drawer was almost the full depth of the counter, or 24". I had it cut to about 14" as the ventilation on the GE unit is at the rear. I still have decent drawer space for my silverware (I did have to relocate a few things but not too bad) but I think I decreased the risk of burning out the electronics. I have noticed that when I turn off the unit and open the drawer I can hear a slight humming for a minute. It sounds like a small fan is under there for ventilation. As per the GE recommendations I do not keep combustibles under there either.

The Wind Crest and I believe the Diva only require a 2" clearance.

I have just finished a kitchen remodel and installed a Miele induction cooktop. It requires a 4" clearance. I have a utensil drawer and 2 large pots and pans drawers under my cooktop and everything works great. Clearance requirements was my deciding factor in induction selection.
According to the appliance store, Miele was one of few choices that had 4" or less clearance requirement.