[...] bans of risky details like bag batteries, silly little charger connectors used for multiple voltages, lack of proper waterproofing etc would all help.
We need to be careful when talking about charger connections to distinguish between two separate situations.
There's a million or so ebikes in circulation, ~ 7 years worth of current sales. Many have an inadequate BMS that leaves the battery vulnerable to overcharging and for those legacy bikes it's right to stress using the correct charger.
Accordingly what we want from future regulation is that batteries have to have built-in electrical protection from overcharging, as nearly all recent batteries have in their BMS. They'll be safer still with more accurate BMS performance ('dynamic modelling') and as you say robust charging plugs superceding barrel connectors. If that's done right the voltage issue (and
much besides) goes away.
Proprietary plugs or comms add a degree of anti-tampering but that comes at a cost. They aren't essential to safe or fast charging, you can have a second layer of over-charging protection without them, they let brands turn an otherwise serviceable product into future e-waste and they make a needless hassle out of charging. In mandating them the Battery Safety Bill
makes a loophole for less protected, less safe batteries than at present, ineptly applying yesterday's fix to tomorrow's situation while ignoring the bigger problem.
Many of the 'institutions' don't seem to grasp the distinction: in future mandate better BMSs; until then fund those targeting advice at high risk groups, advising cautious charging or to upgrade their battery.
