The big one for me is grep/ripgrep. I'm a dev, so there are often times I need to search the contents of files to figure out where something obscure is mentioned. This is also possible on Windows, but as with most things on Windows, it's slow.

The second mention-worthy thing is, oftentimes in conjunction with grep, is piping! It's so enjoyable for me to find the files/content, pipe it to anything (sometimes through xargs and/or tee), so that I can replace the text en-masse with sed, remove all junk files that match a certain parameter with rm, and generally automatically act upon something that I don't have to manually look for.

Although I'm a dev mainly on Windows, I've installed WSL as a compromise, and quite often find myself using its bash to perform tasks like the ones mentioned above.