The problem is manufacturers not the user. The Ioniq charges at 45kW until 80%, then 20kW to 94%, then stops. Cable is free to be removed.
So cars should stop charging below a reasonable level, Rapid chargers should not go below 7kW.
So if a PHEV plugs in it will either not work or stop. i3 cannot sit at 1kW etc.
To my knowledge there is nothing on a Rapid to show kWs: it is usually calibrated in volts and amps. C.7.6kWs equates to 32 amps on a domestic single phase charging circuit but not on a Rapid :the amperage on a Rapid would have to fall below c.12.6 amps to be charging at a lower rate than a standard 7kW post. (based on my last rapid charge at a notional 395 volts).