>>36674436>haptic feedbackIf you can figure out a way to apply strong, flexible granular pressure on fingertips in a convenient and cost-effective manner of course everyone wants it. Closest is maybe ultrasound.
>electric signals for taste and smellYou can't get that without literally opening up the skull and running wires into the brain to do things we barely understand about it. The level of understanding you need to manipulate the brain that way would ensure you see expensive treatments for neurodegenerative diseases appear long before this became possible for recreational use.
Something that has been 'in the works' and theoretically possible for years is galvanic vestibular stimulation which, with electrodes attached to the correct spot near the ear, can induce balance changes which might be able to fix motion sickness, but the problem is trusting users to fix the electrodes to the correct spot and not shock themselves then complain, or worse, have it malfunction and kill them by making them crash into a glass table or fall out a window.
