As someone who learned Elixir during the Phoenix 1.7 release, let me tell you: If you downgrade to Phoenix 1.6 and learn from there, you should be fine.

The upgraded versions are mostly the same, but the differences in Phoenix 1.7 are enough to break the tutorials enough to confuse a newbie. Now, in the post-LLM age, that's not nearly as bad. But it was a real pain when I was learning.