It seems that my Ubuntu 20.04 has slowed down the cursor blinking. Even if I go to Settings → Universal Access → Cursor Blinking and change the Speed, it doesn't help at all. I even tried switching cursor blinking off and on, to "reset" it. Didn't help. It's very unpractical to have to wait for a second or more before you know where you are in a text editor!
You are right to be frustrated. The Settings → Universal Access → Cursor Blinking → Speed option works counter-intuitively. The option should have been named as "time delay" or something, instead of Speed, since what the parameter changes is the delay between consecutive blinks.
So you have to actually reduce the Speed, by dragging the slider to the left, in order to speed up the blinking.