While I agree on principle, we're not always using big-name websites. The argument falls short for some-local-blog.com, there's no security improvement on clicking that link as opposed to shortener.tld/blog-link. I'd say we should trust the source of the link instead of the link itself. Link shortening can be useful if you want long links to look nice when sharing, or simply for personal use so that you don't need to remember long links to access an internal resource. Or just for personal websites. I can link my CV at https://domain.tld/cv instead of the full PDF file path, for example.

It's about trusting the source/sharer.

My friends and family trust me, so trust links I send.

And people currently use public link shortened, this is at least an order of magnitude (or more) better than sharing our data with those people.

It's useful for sharing links over the phone, in person, or on a powerpoint or whatever, though. Or putting links on a business card. I use one for all of the above.