I disagree. Many hard working people are practically invisible and get kicked when there are layoffs. I am not linking layoffs directly to invisibility, but I'd argue that promoting yourself and being known and liked by the important people at your job gives your position more security.

As an example, if you often hop on calls and assist team members, let it be known to your manager. That's self promotion.

Collaborate with your PO. If your team presents their work to other stakeholders regularly, volunteer to present. These are different ways to self promote by simply doing your job.