My 3 19.2kW EVSEs load balance together, so the total draw on the grid is never over 19.2kW. When 2 cars are charging, each is only allowed 9.6kW. When I need faster charging, I just unplug all but the EV that needs to charge faster (or make sure the other ones are not charging via a phone app). The grid doesn't care if I charge 2 EV's at 9.6kW each, or 1 EV at 19.2kW.
The argument on the weight is just silly. The on-board-charger is the exact same size and the weight is listed the same between the 2 parts, I suspect the sizing up of the MOSFET transistors, or maybe adding a couple, doesn't add any significant weight. I'd be willing to bet that you can't tell the difference between the 11kW and 22kW versions by just weighing them, especially if you just took it out of a live system so it may have some liquid coolant in it left.
Offering to replace my 3 AC EVSE's with set of load balancing HVDC chargers, installed, it not going to be $3K. $3K is a cheap Chinese hardware only. Higher quality 20kW HVDC run $10K+. I say replace all 3 plugs because the car is connected to different plugs at different times, but even if I was to agree to just one, it will not load balance with the other AV EVSE's. That said, for my specific usecase, replacing the AC EVSEs with 20kW DC chargers would be acceptable, since 19.2kW on-board-charger is primarily useful for me at home (there is one place outside of the house where I used to charge at 208V/80A, so 16.6kW where I'd be reduced to half of that, but there is a new HVDC charger now available nearby I prefer to use anyways as its way faster). That said, even just one DC charger installed at home costs would be significantly higher than $3K, probably at least $20k all inclusive.
I know at least 2 EV owners with solar who use their 19.2kw (and 22kW, as one is in Europe) to charge the car from solar, and halving the charging capacity makes the car unable to use solar during its peak production, so they would also require DC chargers (which interoperate with their solar) or perhaps a battery storage system installed and paid for my the car manufacturer to store the excess solar and then transfer it to the car later.