Broken internal links that stop crawlers finding pages on your site is generally worse than outbound dead links, which are just inevitable on large sites that have a lot of content and outbound links. It is always nice to find and fix broken outbound links, but its not a critical issue unless the majority of such links are broken. That said it’s probably one of the next best things to fix, after critical issues are solved as it shows you’re keeping on top of content; keeping dead links is a sign of editorial neglect.
We would usually bunch infinite redirect loops in with the worst kind of broken links, as they are very similar in effect and slightly worse even.
When a redirect is being used, and page A links to B which links to C, it’s not technically a broken link, as there is a join, and it’s a very minor issue to update the link to point directly to the end destination. It increases page speed and maximises link equity transfer, but it’s not as major as a broken link. In fact when people use URL shortening tools they’re willingly causing exactly this problem.