Really don’t understand why GUI Emacs uses “fat” cursor. It’s bizarre. Look at screenshot below for 1 second and tell yourself what text is selected.
It requires to think, and it sounds disgusting - to think about so simple thing.
As usual, Emacs has the option to fix it, but defaults suck. I just copied stackexchange solution and forgot about fat cursor’s hell.
In my config I use more thin cursor, with the value of “.2”:
(setq-default cursor-type '(bar . 2))
(set-cursor-color "#FF0000")