Have some respect for your centaur leader!
BTW, there's a distinct difference between Biden's and Trump's flubs (I know because my wife has medical issues that causes her word issues).
Trump stumbles over pronunciation which is why words sound slightly off of correct. Somewhat like a non-English speaker mispronounces words that they've learned, but haven't used frequently with native speakers, which is why words sound slightly off of correct. Whether that's caused by talking without forethought, talking too fast, or just plain using words he's unfamiliar/uncomfortable with using, I don't know. In any case, there's no indication of mental decline, just vocabulary stumbles. At the absolute worst case, I guess you could make the claim that his mental acuity (speed) has slowed to the point where his verb spew outpaces his brain's ability top accurately send muscle movement commands to his mouth, but it is in no way an indication of mental decline (it's either physical decline or he's always been this way and the stresses of the job impact his speech abilities)
Biden on the other hand pronounces words correctly, but mental "earthquakes" (i.e. dementia) causes complete loss of his train of thought. He forgets what he was saying, what words he was trying to find, what thought he was trying to express, where he is (both physically and in his speech), etc. He misremembers the past, blanks completely, and frankly sometimes just appears to give up trying. All his gaffes point to mental decline, which is readily apparent when you compare him today to just 4-5 years ago. There are meds that can prop him up and minimize some of the symptoms for short periods of time, and meds that can help slow the progression, but it is progressing and will continue to.
TL/DR:
Trump has poor vocabulary, though he doesn't think he does, and stumbles over enunciation.
Biden has dementia and has exhibited pronounced mental decline.
Wouldn't be surprised either way come Tuesday, but if I had to bet: