Note the different scales. They were really floundering and never got up to anything like their intended altitude. They also continued the crazy-low altitude for over 5 minutes before final impact.
Looks like they climbed and maintained ~5000 feet after takeoff, presumably to figure out what was going on before returning to the airport. Wouldn't call that crazy low.
The interesting question is going to be: why didn’t the pilot abort the takeoff? Did the problem become obvious only in flight, or were the warning signs on the runway before it was too late?
Ah, a control issue would indeed be pretty much impossible to diagnose before V1. That makes sense.
I have heard of issues that were discoverable before V1. Famously there was the Russian hockey team that was killed because the pilot was riding the brake and didn’t abort in time.
