Charging is likely limited to 18W max like last year’s X, and that peak rate isn’t even used for much of the charge cycle.I think that 30w USB-C Lightning charger will be pretty much an essential purchase if you plan on buying the Max. That's probably Apple's thinking too. An extra £84 on your bill.
Apple’s 12W charger for $19 will give you similar overall charging times, but if you live on your phone USB-C can come in handy for fast 0-50% charging. The USB-C—>Lightning cable is $19 and you don’t have to buy Apple’s charger; there are other, less expensive options