While reviewing a LQ post, I found the answer contained a link, purportedly to a video providing a proof requested in the respective question. However the link was presented as a bit.ly "shortened" link.
This has the effect of disguising the real URL's format, and potentially contributes to link-rot, so as a general preference I'd like to see this avoided. Using my new-found hyperlink hyper-vision, I see there are currently 52 posts containing URL "bit.ly" on Main Math.SE (none on Meta), of which 29 are in Answers. (I'll make a CW post to summarize instances of other common link-shorteners.)
While there are legitimate reasons for shortening and branding links, I find it difficult to imagine those purposes applying here (Math.SE or even StackExchange communities generally). However my ignorance is not a wonderful justification for an editing campaign to remove and replace where possible.
A discussion or pointers to previous discussion on this point of policy would be appreciated.