I think those are mostly programming languages grammars - for logs you will likely need something different. And even for programming languages it might be worth to develop a custom grammar depending on your use case (because of speed and simplicity if you don't need to support all the language constructs and perhaps only parse function definitions, for example)
i mentioned the listing because i was surprised to see multiple, what one might consider, non-programming languages listed. it's true there are a lot to go through :) i thought that with many samples to examine it would be helpful in assessing if it were relatively easy to get an idea of if antlr would be a useful option. i did a translation of the clojure grammar in the parcera project (which uses antlr) recently to a peg grammar and it was very straight-forward.
Not my announcements, cross-posting here as I believe they’re relevant:
https://clojurians.slack.com/archives/C06MAR553/p1596540005363400
https://clojurians.slack.com/archives/C06MAR553/p1596540365364400