Since you have mentioned this I have read three more articles and short blurbs about this kerfuffle and _they all_ have used the same "based on Lucene" text when describing Elasticsearch. As you say, Wikipedia seems to be the one true source of this phrasing!

https://en.m.wikipedia.org/wiki/Elasticsearch

While I still think this phrasing is unfair, it certainly seems to be the consensus. At least when measured by Google search results.

https://www.google.com/search?q=%22Elasticsearch%20is%20a%20...