Neither above comment addresses the previous identified rear axle bump steer.
Thrust angle is an alignment problem. Rear toe on a straight axle is a bent axle. Both problems are not bump related.
Rear bump steer on OEM leaf spring setups is an intentional or acceptable chassis design compromise solution, and only corrected if unneeded or undesired by modifying the suspension, and not changed by simple alignment changes.

Reality check, that half the population is smarter then 50% of the people and it's a constantly contested fact.