Something I figured would be helpful to mention here is something some people likely haven't picked up on yet and that's a manufacturing change for Tamashii Nations.
Jiren is practically infamous at this point for how his arms will snap off if you're not careful, as the top piece of the peg will wind up getting stuck in the shoulder. Another thing said about Jiren is that his plastic is noticeably cheaper than figures of the past.
I'm not an insider of Tamashii Nations, but I don't think any of you have to be in order to pick up on this:
That's right. S.H.Figuarts figures are no longer being made in China, but Vietnam for some reason.
Now, call me a fringe conspiracy theorist or whatever, but given that Jiren had overly stiff joints, fragile arms, light plastic, and was the first to mention being made in Vietnam, it's almost undeniable that Jiren's quality control could be chalked up to cheaper manufacturing. Nothing (to my knowing) has been said from Tamashii's end at the moment, but I'm willing to bet that they chose a Vietnamese manufacturer to cut on costs over their original Chinese manufacturer. Jiren's production likely ended sometime before the whole COVID-19 pandemic and unless the people at Tamashii Nations are psychics, I'd say this was an internal decision to cut on costs.
Note that Jirens started cropping up towards the middle of January. Thousands of these were likely made before this month. Note that Tamashii has thousands of people working on multiple projects in these factories and Jiren was announced in July. Given that, I'd say Tamashii signed off on their original manufacturer before production started on Jiren in order to allow the Adventure Begins Bulma to be produced, but cease ties with this manufacturer for Jiren. Could be some holes in that theory, but this thread was created for a reason.
Yet another thing to add onto Tamashii's streak of laughably lackluster QC blunders I guess. I personally believe this manufacturing change is likely going to affect the quality of these figures, but we'll have to wait and see. Besides, only two figures have been made from this new manufacturer...