Contemporary Amperex Technology Co., Limited (CATL), the largest battery manufacturer in the world with a 38% share of the global market, has just announced some fairly significant breakthroughs in battery tech that aren't just theoretical; they're already hitting the market.
300 kW chargers are pretty common here (Denmark), I did a search, and the fastest I can find is 400kW. But they are rare, and I don’t think many cars can utilize that yet.
I have no doubt that when cars that can handle 1MW become common, we will also get the chargers for them. But it will probably also be expensive to use.
China doesn’t have 1MW yet either, BYD has just begun building them. The fastest Tesla supercharger here is 250 kW.
Ionity has 300kW chargers in Spain but there are pretty rare. 50kW-100kW is most common here. Rolling out 1MW network will be very slow due to all the infrastructure it requires and judging by the prices of 150kW chargers, charging at 1MW speeds will probably be more expensive than gasoline. But in the end that’s the only way to actually replace gasoline cars so they will have to build it eventually. My guess would be 10-15 years before you can reliably (as in network big enough that you can easily find working chargers) charge at those speeds.