I think the lean is expected, I’ve been predicting it. The vehicle lands on only one engine at the end which is off centre, so the landing legs are going to get asymmetric forces on landing. Also these are only interim leg designs.
I very highly doubt the lean is expected. The fact is that 2-3 of the landing legs deployed but did not lock into their extended position, which resulted in the lean this time. This also caused structural damage to the engines and tanks, causing the rupture and kaboom.
Tons of amateur space nerds are analyzing every frame of video that's been gathered about the incident. Here's a gif [1] posted on NASASpaceFlight but originally shot by LabPadre that shows that some of the legs on the left extended and then flopped back and forth a bit, whereas the ones on the right extended and stayed that way. Commenters on Twitter have also pointed out the same [2].
What an achievement SpaceX!
Next test?