Yes, exactly, for EVs to squeeze those extra miles this is what they do now.
How ?
I wish you well trying to keep it at bay by simply braking, but I've never found this to work very well if there is any serious corrosion, and if there is not serious corrosion then it is probably just splash marks of no consequence. Good luck with that, but I recommend heeding my advise, the simple step of just cleaning up the brakes every year or so.
I think you're confusing severe disc rusting (which use won't shift once it's there) with a very fine surface layer of rust that can form within just a couple of days. This interferes with the interface between the pad material and disc causing a large loss in sensitivity.
The situation is exacerbated because often people, including garage techs, merely examine the amount of pad left as indicative of the need to service the brakes.
People here do it routinely; "Hey, my brakes are great, don't need to be touched, only 25% worn in 5 years!". Yeah, and just wait for those frozen calipers ....
Yes, I groan a bit every time I see EV fanboys constantly claim that the mechanical brakes in EV's last near on forever compared to an ICE. Yeah, the pad thickness does, but the discs corrode badly through lack of use and this is more insidious because it results in exactly the surface corrosion and lack of sensitivity this thread is discussing.
That wear that everyone complains about on their ICE discs and pads is exactly what keeps them in good healthy, sensitive, functioning condition.
EVs may never wear their pads in their whole lifetime, this is not a way to perform some sort of brake inspection, so the only way is to strip them down periodically.
Or use more suitable materials than cast steel. It's not rocket science. Steel is used because it's cheap, and it does the job adequately. It's not optimal even in an ICE and its far from optimal in an EV where corrosion build up through lack of use is a major issue.
Eventually I think we'll start to see EV's use materials other than cast steel for the brake discs, however it will cost more, and at the moment EV's cost so much to produce that manufacturers are willing to skimp on much cheaper items than brake discs, such as the plastic on dashboards in a desparate attempt to get the price down. So I don't think we'll see fancy brake disc material on regular EV's for a long time yet until manufacturing costs are under control.
Another option would be to add more intelligence to the brake controller to disable or reduce regen and use the friction brakes periodically to keep the surface rust worn down. Basically the same thing I'm doing now manually but done automatically for the driver without them having to change their pedal control behaviour.
It doesn't take much use of the brakes to keep them clean. I found a total of about 15 seconds of firm friction brake only force per day is enough to clean them up, so over an entire days driving this would not be much loss of regenerative potential.
Think of it like the automatic DPF regeneration cycle in a Diesel car - the driver is barely even aware it is going on, but it's important to keep the DPF working correctly.