This sounds like a guest that wasn't paying complete attention during the booking process. I wouldn't view it as a lost booking - it's someone who was booking out of their price point.
Taxes aren't excessive - it's just a nature of doing business. The airbnb service fee is more subjective but their platform, their rules!
I actually think airbnb does a nice job of controlling the optics on the guest and host sides separately - by not giving insight into taxes/guest fees, we get a clearer picture of the actual income instead of an inflated number. There are financial reports you can access through the dashboard that show you the total amount being paid, however.