Foot operated parking brakes are a PITA (looking at you Mercedes) and electric handbrakes are a pointless complexity that can help you on hill starts if you are a bad driver.
Both of these work well with automatics. Less so with manual gearboxes.
I agree electric handbrakes have added another level of complexity to something that was simple, but when they are working they are easy to use and free up quite a bit of cabin space.
On the new Mercs for instance you never actually use the parking brake. Turn the engine off and the parking brake goes on. Put it in drive and move away and it goes off.
If the battery goes flat you are FUBAR.