I think sample variance may be the primary reason reports vary. I have two Starbounds now. The first one was bought new five or six years ago. It has been an aggressive dumper since day one. While standing, if I bump the chair even slightly the seat will instantly slide all the way to the ground. There is zero problem while downward force is on the seat, but without that leverage the seat is a hare's breath from falling. How I dump myself is by bumping the seat with the backs of my thighs while sitting. If my thighs touch the seat before my butt does the seat flies to the ground, and then I follow it. This tends to happen in winter when I'm wearing my arctic coveralls, which are large and cumbersome. The chair has also dumped one person at outreach. I avoid the dump by pressing my fingers down on the seat before I sit. That little bit of downward pressure keeps the seat from falling.
Chair number two, bought this year from the same vendor, seems like it couldn't possibly dump anyone. There is so much friction it's a bit fussy to adjust the seat. I can lever the seat into the "unlocked" position and it will stay there. It doesn't slide an inch, much less all the way to the ground. As you might imagine, I prefer this seat. At some point I will examine the two and figure out how to rig the dumping chair so that it behaves like the other. I don't see any obvious difference at a glance, but the dumper is white and the safe one is black. That detail is probably irrelevant.
Anyhow, one should not assume that if his chair doesn't dump him that the people who get dumped by the Starbound are fools or otherwise use the chair improperly. In my case, at least, I have two chairs that seem to have been machined to quite different tolerances.
Well first I would say that while being dropped to the ground on your behind can have serious ramifications for some individuals and is not funny, generally I find this thread to be rather humorous.
I would agree that user error or being a fool is not the reason why the chair will send someone's behind careening to earth, however your post best exemplifies what I was looking for. I am trying to find out if the newer (since at least 2018) chairs have tightened the tolerance on the rubber bumper as to avoid an easier release to hopefully mitigate risk of a drop.
As you have explained, my chair acts exactly as your new chair does. Very hard to get it to release. I had second guessed purchasing this chair based on the information regarding it's touchy grip. After seeing a report that a user's new chair was harder to adjust than his old one, correcting the higher risk of dropping, I went ahead and purchased the chair.
By my investigation it is very unlikely that my chair at least, will unexpectedly send me to the ground.
Essentially what I am trying to figure out is whether the tolerances between the frame and the rubber bumper bar been tightened by the manufacturer. Because on my chair, I can lift the seat and it will not drop unless I physically guide it down. The weight of the seat alone is enough to engage the bumper against the frame.
I feel like the thread has utility for those who wish to purchase this chair and may have back issues or have other high risks associated with such a fall. And that if in fact the chair has been slightly modified by the manufacturer to mitigate risk, we can provide at least some anecdotal consensus to help someone in their risk analysis. Ultimately this thread will be probably resolve into people's opinions about whatever chair they already own. However one member did purchase a starbound based on this thread so then again, maybe our conversation here becomes important after all.