Narrative blocks have long taken the place of thought balloons in comics. It's not the same. They're like cleaned-up journal entries. Actual
thought balloons expose the real truth. Case in point, the below panel is from
The Brave and the Bold #64 (1966). Batman
looks tough as he crumples a hastily scribbled note, but on the inside...

Who indeed.
I'm pretty sure he still thinks like this, but "the man" won't let us see it!