Looks like it’s more of an issue with running incorrect track bars.This is actually well documented by many established TJ owners and is a real thing. ARB, OX, Riddlers, and solids to name a few. My ARB front cover hit with the JKS and the Currie correctlinc. Google it and find out for yourself.
I run a very thick front cover and no issues at all. Everyone I wheel with uses the covers you just named with no issues.
In fact. A few members run ARB front covers with currie correct link modified for high steer on Currie and prorock Dana 44s. Still no contact.
It looks like in those examples you pulled... they had an odd track bar situation.
I’ve run covers with the stock track bar and aftermarket metal cloak track bar. Never an issue. Currie track bars also don’t have an issue.
Those axles also look like they are to forward as well. As the TJ/LJ track bar rides in front of the axle housing in the stock position. Not on top. Could also be compounded by not having correct bump stops.
I’m not saying it doesn’t exists. But to say that you can only run stock covers is completely false. Literally millions of jeeps running aftermarket covers and no issues.
Stock covers are pretty thin. One good hit could mean a bad day.