Not a voice of doom - just noting.
Many on this forum don't want to hear it, but MFT is on a long downward trend. Two reasons that I can think of: (1) mirrorless is increasingly being targeted to pro and prosumer cameras, and those are mostly FF, with Fuji being an exception. Pro and prosumer use of MFT is unusual these days. (2) Mirrorless ILC is declining in general, because of phones.
When OM System reaches the point when it's no longer a sustainable business, that will pretty much be the end, with a long tail.
^^^ The voice of doom
Mirrorfull ILC are also in decline, Mirrorless ILC are not unique. Photography as we know it is in decline. It is a hill we've been walking down for a decade.
Not so much a decline as "not needed" and also with the casual photographers quite happy with their phone cameras. The lack of new killer features to justify updating the same thing with yet another makeover series leaves not a lot to market and as the cost of most product steadily increases due to lower market demand, the demand gets even lower.
We should be happy to be able to buy a camera today that will serve us well for over five years and maybe quite a lot more years after that as well.
The manufacturers see video as being the most likely area of photography so they are pushing this. There are some spin off advantages for stills shooters from video enhancements.
I am possibly wrong but I don't think that there is enough video market to sustain the camera industry on its own.
Stills shooters are seen as "old fogeys" but geriatric or otherwise you cannot make them/us buy a new camera body for enhanced video features alone. Don't write off the stills shooters as irrelevant. By and large the old fogeys have more money to spend on cameras. Furthermore do we really think that we can keep the industry rolling along by regularly buying made-over series of expensive camera bodies be they stills orientated or video orientated unless we can see a cost benefit in exciting new features that make such investments worth while.
Otherwise the update market might be replaced by those merely replacing worn out well-used kit. On that basis the GM5 might be due for a replacement as it has served well for near 10 years now. Arguably they are now approaching end of service life and still remain a unique and desirable niche product.
Consider just how much the confirmed GM5 user has saved by not being tempted by an updated version every few years ... The G9 has had a decent shelf life and I would suppose that the G9II is going to be expected to serve well for at least as long. This makes the annual cost of ownership of the GM5/G9/G9II (and other similar long-lived camera bodies) much more affordable.
It also makes cameras such as the low-cost but quite additive G100 type even more enticing. I am expecting my G100 bodies to last as long as my GM5 bodies. Really? Yes "really". The simpler but effective camera bodies have less need of being updated. The small changes now marketed as the G100D seem a natural in production update rather than a new model type.
My G9 is far from worn out and the G9II is just a very refined version of the G9.
It is hardly surprising that digital camera users are tending to keep their much loved gear for longer periods of use. One might wonder just how many series of made-over versions of much the same thing that Canon and Sony can foist on their devoted customers before they are also forced into less frequent updates.