Have you ever tried $X - > member (where $X is an instantiated class object?)

That's not whitespace around operators. That's replacing one operator with two (minus and greater than). Of course that'll make a difference, but my point was that whitespace around the operator currently doesn't and shouldn't in the future. Don't misconstrue it. To be clear, the reason meaningless whitespace around operators is is that both of the following work the same way:

$a->someMethod()->someOtherMethod();
$a->someMethod()
  ->someOtherMethod();

Now, though, you're proposing that namespaces shouldn't be allowed to have the same name as any variable, class or constant. Are you mad? You realise that name conflict resolution is what namespaces are for, right? Yet you want to make it the case that if I'm using a Date namespace, I can never have a variable or class called date/Date? That's crazy.

The "just make sure your names are memorable, distinctive, and you're good to go" rule is what PHP currently has, with class names for instance. And it's the problem that namespaces are designed to solve, not make worse.