The problem with Biden isn't just dementia. It is Biden was perhaps one of the most idiotic senators to have ever served on Congress. He was petty, small minded and dumber than a mud fence and has anger management issues.
Now, on top of all of that, he now has dementia.
When Obama was running for president, Katic Couric, interviewed Biden. Somehow they got on the subject of Franklin Roosevelt. Biden talked about how FDR comforted the nation on TV after the stock market crashed in 1929. The only problem with what Biden said is that in 1929 FDR was the governor of New York, not the president. The president was Herbert Hoover.
The other major problem is that the television had been around before 1929 (it was introduced to the world at the 1928 Worlds Fair) but there were no nationwide broadcasts until much later. It wasn't until the 1950's that TV's were found in most homes. So literally no one was watching FDR comfort anyone in 1929. It just did not happen. They might have listened to Herbert Hoover try to comfort the nation on a nationwide radio broadcast but that is not what the idiot Joe Biden said.