[HS] Terminal lists all commands on

So last night I spontaneously erased my fully working Sierra hack and did a fresh install of High Sierra from scratch.

I did scratch my head a lot last night.

Anyway, it all went smoothly, surprisingly. But now, while I'm on the terminal, whenever I press tab twice, it lists all 1700+ binaries / commands available. I don't remember it being like this on Sierra.

Thoughts?