That's a bit of a long read, but when you get down to the bit about cost per mile, home charging just about beats diesel, public charging is much more expensive than diesel or petrol.
Due to various circumstances, we have now taken the iX Fugly wagon to just over 6,000 miles since late June. In that time we have mostly charged at home with a smattering of free charging at my work (competition for the small number of spaces means I often CBA to get there early enough to guarantee a space).
Excluding freebies, the car costs 7p/kwh to charge at home and is doing an average of 2.8 miles /kwh. Which is not amazing but means it costs me 2.5p/mile worst case. A diesel equivalent car (assuming diesel is £1.39/l) would have to do around 253mpg to deliver the equivalent fuel cost.
In terms of overall cost, the car is £560pcm for a fully maintained lease for 20,000 miles per year. Add in the electrons to do those miles (assuming no freebies) and you get a total cost of £602pcm. Compared to my chrysler, doing the same at 35mpg
Fuel £301pcm
Insurance (£560pa) £47pcm
Tax (£415pa) £36pcm
DIY servicing & MOT (£150 pa) £13pcm
Depreciation (£1000 pa assuming £4k car goes to £1k over 80,000 miles & 4yrs) £83pcm
Total: £480pcm
This also doesn't include any repairs, tyres, wiper blades etc etc.
So I am paying at most £122 per month (likely much less in reality) to ride around in something that's quicker, quieter, more comfortable, brand new and never needs me to lie underneath it on a wet afternoon because something has stopped working. In my book that's pretty good value, and if I went for something less upmarket like a tesla, that £600pcm would be more like £400. For me, the BMW actually worked out cheaper as it meant I could persuade SWMBO out of her Evoque so we went from three cars to two

(Or we will do as soon as I can get shut of the enormous american lawn ornament I currently have the misfortune of owning!).
So I would say they do work financially, but only really as a lease proposition. I would never buy a new one with my own money; but then again I wouldn't buy a new petrol/diesel car either. I would 100% buy something like a 3yr old ev that has been hammered by depreciation as I think they would be very cost effective to run and actually, as a commuter car, are much nicer than a diesel.
Clearly there are horror stories going around with battery packs, many of which I am sure are accurate. But I also think a lot of that is to do with a lack of independents specialising in EVs. So owners' only recourse is main dealers, who don't have mechanics any more, only children with laptops and component changers, and the only component they can change is the entire battery pack. So that's what you get, a new pack.