I think a lot of the resistance is due to information overload. Teaching people about branching, merging, rebasing, et al, is a fool's errand when they haven't previously used source control, or even any command line interface, on a regular basis.

Let's just try grasping creating a repo, committing changes, and publishing them to remote repos (Github / Bitbucket). This will allow people to become acustom to the terminal and just a handful of Git commands to integrate version control into their own workflow, before being bombarded with the more technical commands which create team-based workflows.

To directly answer your questions:

Do you use/don't use a GUI client for it?

No, the CLI is well-written and GUI diagrams just confuse the matter, they force a visual mapping to the workflow that may differ to what's in people's heads.

Do you think it's worth it for small projects?

It's worth it for anything. It's just about educating people so they find it so easy for "should I use Git for this?" to be a non-question.

Do you think it's for everyone?

Everyone who works in the creative / tech space: absolutely. It just needs to be taught in the right manner.