This is a case where both tools are invaluable.

The original find has much more comprehensive options. Of course it is extensively documented and you can find all kinds of information online about how it works and how to combine it with other tools to accomplish all kinds of tasks. And it's GPL which is always preferable.

fd has a narrower range of functionality but goddamned it really is faster. fd can run several searches on the whole hard drive's contents while find is struggling to get through just a single comparable search on the same set of files. For simple tasks, the cli usage for fd is less to remember and less to type.

If I had to choose, I'd stick with find because it can do everything, even if it's slower and more cumbersome. But luckily, don't have to choose, just have both and use them as appropriate.