I don't think the comparison is fair.

The electricity and ICE fuel costs should be included if the battery is included. The battery is some sort of upfront fuel cost in a way the gas tank isn't.

Since mileage wear is proportional to fuel use anyway.

If we were talking cost of ownership, sure.

But we're discussing resale value specifically, and it doesn't matter if you spent $25 or $50 "filling it up" last week when you sell it.

I prefer to think of a battery as a transmission since rebuild/replacement costs and inconvenience are comparable.