Last I checked, tmux binds are all emacs-like until you change your config. I remember the copying stuff suddenly being easy once I toggled the vi-like keys. Maybe you haven't used an unconfigured tmux in a while.
tmux actually tries to be clever here and guess if you're a vim user or not: if your $EDITOR contains the string "vi", you get vi-style keybindings by default. If it doesn't, you get emacs.
But unfortunately it doesn't look at $VISUAL, so... yeah, you usually have to set it explicitly.
But unfortunately it doesn't look at $VISUAL, so... yeah, you usually have to set it explicitly.