sadly mistaken

In this, the great statesman was sadly mistaken.

“Anybody who thinks that not getting on TikTok is going to protect them from something is sadly mistaken. Google, Microsoft, Amazon have got everything they need from us — they probably sell it to the guys at TikTok,” Flores said.

“My friend,” General Garner remembered Mr. Rumsfeld saying, “if you think we’re going to spend a billion dollars of our money over there, you are sadly mistaken.”

If you thought the Chinese spy balloon saga would deflate as fast as the balloon did over the Atlantic Ocean, you’re sadly mistaken.

Wade, but if she thought nobody would notice, she was sadly mistaken.