Kate offers vertical block selection as a toggleable state. I.e. one has to press a shortcut to enable it. Some editors (for instance Geany) offer more comfortable way of selecting a block which is close to the non block selection. That is using Alt + Shift + arrow.

It's quite easy and doesn't require any pressing of the toggle combination. It's also easy to switch in and out of that mode by simply releasing or pressing again the Alt button,

Reproducible: Always