another typo at the same page:

But but careful not to confuse the terms

Should be:
But be careful not to confuse the terms.

Thank you for reporting these typos @MedUnes. I opened #7207 which fixes the second one. Though I do not fully understand which issue you see with your first example. Can you explain this with more details or describe what you would like to see instead?

The two controllers are (listAction() and showAction() ) so the sentence should have been written

"For organization, both controllers (formerly list.php and show.php) are now PHP functions and each has been moved into a separate file named controllers.php:",

instead of

"For organization, both controllers (formerly index.php and show.php) are now PHP functions and each has been moved into a separate file named controllers.php:",

But the filename used before on that page always was index.php when referring to the controller (list.php was only ever used for the template), wasn't it?

if so it might be, though the context is a bit confusing, it might need more precision.

Yeah, you might not be wrong. It's sometimes hard to tell that because of different perspectives. Do you have an idea how we could improve the current wording?

I agree with @MedUnes and I've opened #7838 to fix the remaining issue.