The problem is the logistics of an open search project that is a web service with serious hardware requirements. I think the minimum hardware requirements is about 14 Gb of RAM, that's without any real data loaded into the system. Testing is awkward and cumbersome, and the data logistics are a real headache even on the same network as the production instance.
To even run the search engine, you need a few hundred megabytes of language models, as well as a probably few gigabytes of website data to conduct meaningful testing. The production instance has a disk footprint of about half a terabyte.
My ignorant suggestion towards sharing those gigabytes of data: have you considered bittorrents?
My philosophy to open source is just do my personal projects in the open even if it’s not “accessible” and if someone comes along and likes it they can contribute or fork it and modify to their liking. Or they might just browse the code and pick up something in passing.