Wow, OK.
This isn't rocket science. Most of the S/DS/FX whatever were designed in 2013 for release in 2014. They chose what would fit and what was affordable at the time. They didn't have Diginows then, and the chargers were not as powerful and small. Level 2 charging wasn't nearly as common. By providing Level 1, they gave everyone a chance to own the bike.
Level 2 charging became far more common, and they added 3kW charge tanks as an option in 2017 for all bikes except the FX. Because people wanted faster charging and stations were expanding. In 2018 they took advantage of faster/denser chargers and upped it to 6kW for the same price and form factor.
In 2019 they released the FST bikes with 3kW and 6kW FST charging standard on the bike. And a host of new features. Interesting to me was that they did not use the Diginow chargers, but I suspect they must have run into FCC/regulatory issues, since they're essentially standard Chinese parts with Brandon's controller FW.
Rumors abound, but there's a DSR/X and FX/E coming soon, I'd be surprised if they didn't build off the new FST platform and probably have LV2 charging integrated.
I wouldn't be surprised if they also released a DCFC tank for the FST plaform too, maybe with a speed somewhat above 12kW. Zero likes modularity, incremental improvements, and accessory revenue.
I personally do not think people will buy electric bikes without a place to charge them in/outside their home. I do not like waiting 30m-1hr for charging every day at a charge station. The technology for 5 min refills like a gasser is just not there. It's a limitation of the electric vehicle category itself.
Could they put a faster charger on the FX today? Sure. Would they bump up the price about 1k? Probably. The FX is the cheapest/lightest electric motorcycle in the field today that's not a fully Chinese bike with questionable specs and a nonexistent dealer network. It's not trying to be a medium range commuter, it's trying to be a cheap, overnight charging, dirt capable fun bike.
Wouldn't most of the people in the center of London take public transit anyway?