The Bolt only has something like a 35ah battery, Why would they over spec it's charger?
IIRC, from other threads on the topic, the DC-DC feeding the 12V PbA Auxiliary battery is rated for 1600W. I hooked up a 1500W pure sine-wave inverter at the battery and firewall ground post*, and tried various loads on the inverter's AC output. Anything above ~1kW AC off the inverter output, and the DC-DC couldn't keep up (the PbA battery voltage started to drop). This will vary, based on the efficiency of the inverter.
* You don't want to hook up the ground lead for the inverter at the battery terminal. There's a current sensor at the battery ground, and it will read the excess current draw as a fault, and throw a code. Pick up the ground connection elsewhere. I used the firewall grounding point. Others have used the tall ground post on the middle-top of the motor/electronics block.