Inductive charging is really required for cars with a Frankenplug.How much does it cost to add inductive charging to a car? How much would the typical customer pay to upgrade to inductive?
In the case of Supercharging via inductive, a 10-20% slower charge means they have to build 10-20% more charging spaces and people are waiting longer to charge up. It's also more expensive for the customer, and Tesla would have to accommodate more capacity.
There is a lot more going on that just a small amount of energy loss.
Seems to me like inductive charging is most likely a home charging convenience. Maybe a bolt on accessory for the 3/Y and included on the S/X.