I like my parens in a muted color with the currently active one highlighted.

Rainbow colors are extremely distracting and overloading to me.

I also came back to B&W because I’ve noticed that with structural editing I think more in terms of s-expressions than parentheses and distinguishing them isn’t that much of a problem anymore.

I use these colours for rainbow brackets in all other languages https://github.com/Release-Candidate/vscode-scheme-repl/blob... but for LISPs I dimmed them (their saturation) down for normal editing (when not "recording" animations/videos).

This is the first time I’ve ever seen rainbow parentheses, it seems like such a useful thing. What wound up leading you back to B&W?

Not the parent but speaking for myself. I read Lisp code by looking at the indentations. Parens don't matter unless they're wrong, and they're rarely wrong because my editor matches them as I type, and then I just tell it to indent everything properly. If the indentation looks goofy after that step I notice it immediately and only then do I look for paren problems.

Lisp is by far my favorite language but if I had to write it with a "dumb" text editor it would quickly stop being my favorite. Most editors are smart these days, and this is why it's hard to explain to newbies that the parens don't get in your way: When you build lisp code your editor manages the parens for you and they become essentially invisible. So color solves a problem that doesn't exist (for me).

Probably because you get used to them and different colours become distracting. Highlighting of active parentheses is more useful

Too much visual clutter with very little actual benefit. I found that I don't need/want to find matching parentheses by a mix of position AND color.

Using an actual rainbow seems a bad idea. I will try to set up a Viridis (or similar perceptually continuous) color scheme next time I dabble in lisps.

Golden opportunity to slip an "animated" option in there. I'm pretty sure there are editors with a little jump to the other side of a form to show where it is.

In Zmacs on the Lisp Machine, the s-expression under the mouse cursor gets an outline. This is updated while the mouse is moving.