I.e., some guy showing up and walking around the house for 40 minutes and taking some pictures and writing up a report.

For the vast majority of properties bought and sold in this country, an automated modeling appraisal program could do a better job, wouldn't be subject to the vagaries of human interaction, and would do so at a fraction of the price. You'd still probably want appraisals for unique or hard-to-sell homes, and you'd definitely want them on most commercial real estate transactions. But if you're buying/selling a single-family dwelling in any kind of development or tract housing or suburb or condominium or multifamily or planned community, there is very little value-add from a human appraiser. I fully expect the vast majority of appraisers to be a relic of the past in the not-too-distant future.