Why in the world haven't the major title insurers immediately said yes to this? . . .  

You will have to ask them.

Senior managements of all five major title insurers were given extensive in-person briefings by the FSH Working Group in December, 2001, and January, 2002.  First American management was given two briefings.

All title insurers, regardless of size, were provided with the "Introducing FeeSimpleHosting" presentation document and a compact disk containing all the documents on this website. All were handed written invitations to participate. All were provided Participation Agreement forms ready for their signature. 

The combined national market share of the five major families is approximately 90%.  Under the terms of the FSH proposal a quorum of 80% total national market share is required to move forward.

LandAmerica, the third largest insuring family measured by gross premiums, immediately agreed to participate, subject to the other four major underwriters also doing so.

Fidelity National, the largest insuring family at that time, replied in writing that it would not participate because, among other reasons, it did not believe doing so was in its strategic interests.

First American, the second largest insuring family at that time, indicated that it would be interested to know how others, especially Fidelity National, responded.  It ultimately declined in writing to participate.

Stewart Information, fourth largest, declined to participate in writing.

Old Republic, fifth largest insuring family, did not agree to participate.