It's not true. A lot of people only focus on the CV axle angles and incorrectly assume that since 2WD don't have CV axles that there's no issue with stacking lifts.

The truth is CV axles are cheap, so who cares if you bust those? Whats not cheap is the steering rack which will get beat up operating the tie rods at steep angles. It's also not cheap to keep getting alignments when you have to replace balljoints and tie rods consistently. Not to mention the lack of suspension down travel will result in a crappy ride and even less offroad flex than we currently have.

In other words... don't stack lifts.