Why does psr-1 say to use such a construct?

Question

PHP

PSR-1 tells us:

В файлах НЕОБХОДИМО использовать только теги <?php и <?=.

Why such a genocide against the construction "<?"?

Answer 1

Because with <? Many problems. Rendering XML documents (yes, it happens), some other stuff, conflicts, etc. For this reason, it is disabled by default in php.ini. And for this reason, the standard says not to use this tag at all.

Answer 2

PHP also allows short tags <? and ?> , but they are not recommended, as they are only available if enabled with the php.ini configuration directive short_open_tag , or if PHP has been configured with the --enable-short-tags option.

https://php.net/manual/en/language.basic-syntax.ph...