You example doesn't work because you tried to access the element with a string, which was ALSO converted to an int.
https://repl.it/repls/CompetentBlondInstructions
Here I changed your string index to an int and it still says success!
Re:A look at modern PHP
by withinboredom on Tuesday May 05, 2020 @03:17PM
(#23083720)
Most people don't use a production version of php.ini, I'm fairly certain you can turn this off and on in there. I've only run into this on my personal projects (where I don't care too much about the configuration) but never at work.
https://repl.it/@JadoJodo/SelfreliantEdibleUsers
edit: Not trying to discount your feelings overall, but just curious about that specific example.