Follow up question - what are “normal tolerances” and who decided what value they should be? And how do you measure frame flex as your driving down the road to know that your rig has exceeded “normal tolerances”? Asking for a friend.
Not to be argumentative, but you say it’s a “known issue”, but when I do a search on this forum the only thing that pops up is this thread, a thread about a tow vehicle, and everything else is more than 10 years old. Not at all supportive of a “known issue” claim. I have had some experience with structural issues and frame issues simultaneously. But connecting the dots and assigning and affixing blame may not be as straightforward as you allude it to be. Just my own experience.
As an example, I would point out that you can bend a frame (or flex it inappropriately) by jacking up the trailer to change a tire at the wrong place.