Biden has always struggled to finish his thought before starting a new one. He is a terrible public speaker and always has been.
However, the clip circulating on the right-wing shows isn't a fair representation of Biden's performance Kimmel. Especially this Dore clip, which is presented in a way to demonize him.
That being said, I can't even imagine what the 2024 election will look like if it is Biden and Trump again. They're both old as dirt and both are terrible public speakers in different ways: Trump does three word superficial thoughts, which he jams together loudly and Biden tries to overcomplicate things in thoughts that never come to an end. We definitely need someone younger (sorry Bill Maher... as a side note, I enjoy Bill Maher but he is beyond wrong when it comes to his critiques of millennials and his complaints of age-ism when it comes to old people).