The claim was Ds are more procedural than Rs. Asking what process the Ds followed to attempt to run, and then back out of running, biden (who again, was very obviously and publicly mentally incompetent) is clearly a rebuttal to a presented point.
You can repeat that as often as you want, but it doesn't seem well grounded. He's always had a stutter, and since he left office he has given speeches which suggest his mental faculties remain intact. Is he slowing down? Yeah. He's got quite a long ways to go before he's in McConnell territory.
In any case, what does his choosing to run have to do with process? Did he violate the process? Seems to me he was following it to a tee.