Donor time/attention is a precious commodity to fundraisers, so I wouldn’t expect organizations to have expended much of it on this topic without a specific business justification. It’s plausible to me that the funders thought (and may still think) that each org’s easily-quantifiable output was sufficient to fill room for more funding, and that the orgs didn’t (and don’t) think more precise measurement of indirect impact would materially change org strategy (e.g., because those impacts are attainable by the org only as a byproduct of doing the org’s standard work).
Donor time/attention is a precious commodity to fundraisers, so I wouldn’t expect organizations to have expended much of it on this topic without a specific business justification. It’s plausible to me that the funders thought (and may still think) that each org’s easily-quantifiable output was sufficient to fill room for more funding, and that the orgs didn’t (and don’t) think more precise measurement of indirect impact would materially change org strategy (e.g., because those impacts are attainable by the org only as a byproduct of doing the org’s standard work).