Hmmm I think this will take a while. I have just bought back into DSLR for the following reasons:
Price wise, more for your money
Size and wise, not too much difference with FF
Better AF for my budget
Better battery all round
Lens selection and third party lenses
New mirrorless FF systems that come out will be very expensive for a considerable amount of time, value of DSLR and lenses will take a while to drop. If in the next year or two I start to see a rapid decline in the value of my stuff I may sell up and move to mirrorless. I don't think it will happen like that though.
It could be said (again) we live in changing times.
At any given point, either through technical innovation or temporal fads, we have opportunities to evolve or stick with that which we are comfortable with.
Things change and sometimes pivot back yo the same point. It happened with vinyl through 8 track, cassette, CD, super CD, Mini Disc, then back to vinyl..... and so on.
With photography the technology stayed roughly the same till Digital arrived but the basics were light hits chemical based sensitive plate/film and other chemicals are used to create an image as a negative which was the projected on to chemically treated paper and then put into more chemicals to create the finished article.... phew
Yep that is resurfacing and the retro becomes real again...
Technically on the hardware front huge changes have bought photography into the cutting edge in image capture and the means to transmit and display images.
All great till you look st the design of digital cameras. In the main they still look and feel as they did back to the early rangefinders right through to the SLRs on their release. I adore the retro look and feel of my EOS M6!
The fact is that the technology has moved on and the ‘SLR’ style and ‘nuts and bolts’ mechanical elements begin to look redundant in a modern piece of electronics. It is also both an anachronism and a point of potential failure.
I like the balance of my SLR/DSLR kit, they feel sturdy and practical but yes I have had mirror box failures in both film and digital kit.
Canon’s approch with the M series offers a bit of hope and they are not alone in terms of styling from the other brands but, realistically, do we truly need a mechanical box or is it the ‘pro’ look and feel that adds to the attraction? “My lens is bigger than your lens”!
I like the M5 style but more than that, it is feature rich in a more compact package and with a Sigma 150-60 on it I can hold my head high in the men’s room.
The full frame DSLR size and shape can stay iconic and balanced but rip out the mirror box and build in more capabilities that are beneficial not bells and whistle features.