I think you're saying you enabled the "Enable member-gallery-containers" option, but still didn't see the gallery tab.

You need to edit a gallery, or add a gallery, with "Personal gallery container" set. At that point you will immediately see a Galleries tab on your profile

Okay, I imagined there would be a link to create my personal gallery on my profile somewhere, that's what confused me.

You will as soon as a personal gallery container exists.

When viewing self-profile you see the tab even if you have no gallery yet. For other-users profiles you see the tab only if they have a gallery thus far.