A search engine is technically sufficient, but takes more time and is less accessible. A search engine won't put things in front of you for you to peruse and explore; you have to know what you're looking for. Beyond that, the contributors and I have done research to find and decide on the entries on this list, which should help readers avoid repeating the same process.
A git repo has an explicitly responsible maintainer, while wikipedia articles do not. This helps keep the quality high.
Regarding SEO - even now, the same day I first pushed this, searching 'lua awesome' returns this as result #5 on Google. 'awesome-<language>' is a known convention for curated lists like this one, and people familiar with that convention who are looking for Lua resources will easily find this.