The scenario you describe is malicious because people don't expect a charger to have "features" which consume large amounts of power without benefit, but it does make me wonder if such tech could be incorporated into electrical items whose express intent is to turn electricity into heat.

Say, a clothes iron, or washing machine/dishwasher water heater (where not already plumbed for hot water), etc.

Since computation ultimately dumps essentially 100% of the consumed energy as heat, why not use it for that?

Obvious arguments against are the cost of the initial hardware, and the engineering difficulty of making something which can actually operate whilst generating kilowatts of heat (i.e. not cooking your cores in the process)