Obviously if the project requires working emails, PHP cannot solve it. If I understand the parent comment correctly, what it says is that sending mails with PHP

Obviously if the project requires working emails, PHP cannot solve it. If I understand the parent comment correctly, what it says is that sending mails with PHP is usually less problematic than other languages (IIRC from the last time that I used PHP -several years ago- their mail() function works OOTB almost everywhere, even on shared hosting, and is usually used by default or as a fallback).