@fedisearch this discussion is moot.
anyone could run an indexer without telling the public, and _nobody_ would notice (i bet google and other indexers internall don't give a flying fsck on robots.txt). so my 2 cent:
- opensource it, folks who want to ignore robots.txt etc. will do so anyway.
- if you don't like being indexed, don't put it in the internet, it doesn't forget.