Everything becomes better with fzf. I use it to parse git logs, checkout branches, select and download files from s3... Fzf is the single tool that vastly improved my command line productivity.
Sure, but you're building strings in memory. It might not be a lot of memory, especially if you're able to run Python, but the native `yes` command can run on the smallest of embedded systems, which is why its speed is impressive.
If you want to invert the boolean check, then you need to invert the input space as well, which is not possible.
For example, consider a Bloom filter checking the availability of a username during sign up. If you want an inverse Bloom filter that checks if it is not not in the group, then you need to load it with all possible usernames.