In https://github.com/php/php-src/blob/879cd0491399ccfacac0d6ed701d998a65a6cc97/ext/reflection/php_reflection.c we can see that ReflectionClass::isIterateable() is an alias for ReflectionClass::isIterable().
(PHP 5, PHP 7, PHP 8)
ReflectionClass::isIterateable — Alias von ReflectionClass::isIterable()
Alias von ReflectionClass::isIterable()
As of PHP 7.2.0, instead of the missspelled RefectionClass::isIterateable(), ReflectionClass::isIterable() should be preferred.
In https://github.com/php/php-src/blob/879cd0491399ccfacac0d6ed701d998a65a6cc97/ext/reflection/php_reflection.c we can see that ReflectionClass::isIterateable() is an alias for ReflectionClass::isIterable().