Oh please, give us the name the AMC you shill for?
nobody was held hostage, zillions a record number of loans closed with appraisals, the mortgage lenders will remember that time as their last big boom rich time to and wish they had that tiny problem back of waiting a few days or in some cases paying a bit more to get the appraisal done
Appraisers were swamped and so they could not deliver as fast as normal, so what everybody who wanted to refinance or buy got to do it, as far as "high" fees that was true in some cases but everyone else in RE was charging high commissions or fees.
The lenders will not benefit from any tech advances wrt valuations because very other lender will have the same so they will all be equal and then they still have to compete out there for a shrinking or stalled market of people taking loans. The real problem for lenders is not how fast or cheap a valuation is, they can be free and in one minute done and it won't help a lender who does not have enough volume due to interest rates or over-competition from other lenders -