I'm just going to make a post here, and I'd like it if
@Deino could move this post and the last few OT ones into the thread I linked to in my last post.
So regarding the question about flight suits, there are certain elements we need to consider.
First there are the "flight overalls" themselves, which is essentially a one piece jumpsuit. Most western air forces use dark green, and the Chinese military is transitioning to dark green overalls as well, but they still have a good number of blue flight overalls... obviously, because western air forces and pilots are most often seen in action, green overalls have been psychologically conditioned to look "cooler" and more "modern". For instance, when we see a Chinese pilot and a Pakistani pilot shake hands both wearing only flight overalls, the Pakistani pilot looks much sharper, simply because he's wearing green.
Second of all, we have the question which Ultra brought up, which was the issue about the flight jacket and flight vest itself. Flight vests come in various types, some are life preservers with floatation devices built in, and some have survival gear (knives, even firearms) carried on them, and some even have redundant oxygen gear on them probably in case if their onboard life support fails.
The above flight vests that I've seen most commonly for western air forces include floatation vests and/or survival vests, and this reflects two things I think:
1: relatively high investment per pilot, compared to other air forces (including China, but also until recently, Russia) -- that means they're able to give their pilots a lot of the additional goodies that are probably not "essential" to their roles like survival vests or floatation vests. OTOH, more essential equipment such as G suits (which are obviously essential for air combat), tends to be relatively standard equipment for pilots even for poorer air forces
2: western air forces generally operate over international waters and territory abroad more frequently than the air forces of say, China or Russia, meaning floatation vests and vests with survival gear is a much more consistent need than say for China or Russia whose aircraft mostly operate in and around their own air space... although if you look at Russian pilots operating in Syria, their flight vests are a bit more complex than what many of the Russian pilots operating in their home country commonly fly with.
In the case of the Chinese, the most common standard equipment they have seems to be a relatively simple harness that can strap a few pouches onto them (possibly for rudimentary survival gear and an expandable floatation vest), and this is likely because of a combination of relatively low investment per pilot (until recently), meaning less important items like higher complexity flight vests are less important, especially when most Chinese pilots do not operate anywhere over water or foreign/hostile territory.
However, even pilots for aircraft as old as J-7s have had g suits, which we can see for the last few years, meaning the military clearly understand what the most important items are, and are willing to forgo more unnecessary equipment until later.
Now, with recent developments, such as more consistent Chinese flight operations over the ocean (especially by naval aviation fighters and the induction of J-15), as well as higher investment per pilot overall, the military can now afford to buy more complex life vests for their pilots, and also to fulfill their new missions that they'll perform more often:
Finally, with regards to the "jackets" -- they are flight jackets, and while they look somewhat reminiscent of older "bomber jackets" from WWII, flight jackets themselves are not obsolete, but in the west, they are made of materials like nylon, and included the older G1, MA-1 and the more modern CWU-45 and CWU-36. Their colours are more consistent with the likes of their flight overalls, so when pilots wear them in the cockpit (and they do), they are harder to spot. And no, they generally do not remove flight jackets inside the plane.
In the Chinese miltiary's case, I don't think there's anything particularly wrong with wearing flight jackets that look the way they are, so long as they are functional. If anyone wants to laugh at them only because of how they look (and tbh they look fine to me), then I think that is their problem.
