Interesting, hadn't seen that last clip. He only starts swerving there after he's past the bulk of the crowd and deliberately fails to hit the officer. The route is also pretty close to what I was speculating about the panic state and getting the fuck home.
Taking into the account the above video, I'm pretty sure that he hit a panic state at some point. For the record, what I'm describing is a phenomenon that typically sets in at a heart rate somewhere between 145 and 175 bpm, depending on the individual in question, where the heart is beating so fast that it is unable to take in a sufficient supply of blood before pumping, causing a rapid drop in blood pressure and symptoms similar to asphyxiation (hence, fainting from fright). High-speed driving is a stressful activity, with NASCAR drivers regularly pushing the limits on this factor, so once he gets into this state I have no problem seeing him staying there until his capture. The question, then, is when he enters this state, to which I see 3 possibilities:
1: During or after the alleged stabbing, as I initially proposed. The stretch on this possibility is his prior history, since a rap sheet like that would suggest he has some degree of inoculation to not freaking the fuck out when doing a violence, if only through repeated exposure.
2: Passing the first cops to sight him. He was already speeding at this point, potentially under stress from the stabbing, and seeing a cop sends him over the edge.
3: After hitting the crowd. If he was doing a terrorism, then the multiple groups on foot he missed are still a question mark, with the best explanation likely being last-second hesitation until the old ladies being all over the street forces his hand. When the rush then hits him, he overloads, forgets that he's trying to do a terrorism, and defaults to muscle memory, leading him to swerve around the cop instead of picking up one more kill.
I dunno. The evidence for terminal stupidity is circumstantial, while the evidence for terrorism is pretty damned weak in comparison to the shit we see on other social media accounts. If he was going for a high score, he did an exceptionally shitty job of it, but at the same time that tends to be a pattern with people that do try.