Ditto. Today's PHP is not your what your grandfather used to use. It's a much matured and evolving language. Python only got so popular due to Google's use and AI. It's like the new Perl.
Author talked about usability problem with database, it's oxymoron usability problem in this site where all the text are in gray which makes reading very painful. Had to use "Darken Text" Chrome ext so it is not killing my eye!
I did some digging for you, I am not the best at Rails but from my understanding, it seems to throw the queries into ActiveRecords QueryAttribute using bind parameters [1]. So I'd say enough safe from sqli [2].