If you ask me, if changing systems doesn't imply spending a lot of money, which is and isn't true, depending on lots of things, it all comes to EVF. I'm one of the guys with headaches from EVFs and it took me a while to adapt to EVFs. I started to play with mirrorless cameras early, when the A6000 was released and with each generation of mirrorless, EVFs improved up to the point that now I'm 97% ok with EVFs. The only mirrorless manufacturer that is behind in terms of EVFs is Olympus.
Aside the fact that I was playing for a few years with mirrorless cameras from different manufacturers, shooting side by side with a mirrorless and a DSLR that have quite similar specs for 6 months already, I realized that my DSLR stays home 90% of the time. And it doesn't stay home because it doesn't do a good job because it does an excelent job each time I grab it, but since I shoot quite a lot wide open with fast lenses, it's easier to work with mirrorless for 2 reasons:
1. Eye af
2. I don't have to focus and recompose which is tricky at f1.4 with people that don't stay still
Despite the fact that the weight difference isn't much between my 2 cameras, the size of the mirrorless it's less eye catching for people at corporate events who are still used to big and bulky cameras of photographers, with flash on top.
If I were a guy shooting lanscape or stodio, live view of DSLRs would have been the mirrorless option and I wouldn't be that much interested in mirrorless...
Mirrorless seems to pack more features in their cameras: focus stalking, eye af, pixel shift, both silent and normal shutter, better video, etc. Looking at 1Dx Mark III for example, it seems a little better (just a little) at tracking in live view due to eye af and larger Af area selection. This makes me think that DSLRs won't have much of a life in the next years, at least when comes to the 2 big DSLR manufacturers (Canon and Nikon). They will most likely release 5D Mark V and D860 due to the still very large user base of DSLR shooters. But 5D Mark V will have to be very solid to beat EOS R5 specs for example and shift the attention of users from mirrorless to DSLR.
At this point, I really don't know which approach would be good for Pentax. Focusing on DSLR means that probably they will remain alone in DSLR market after Canon and Nikon will concentrate more and more on mirrorless and "force" their users to switch to mirrorless. This can be good or bad for Ricoh... Good because of the people who want OVF in their cameras with all costs based on the current EVF options in other manufacturer cameras and bad because we don't know how EVFs will look like in the next 5-7 years (the improvements from Sony A7 to Sony A7R IV in terms of EVFs are huge) and because Ricoh isn't known for marketing their cameras either. And then comes lenses... Now there are quite a little modern Pentax lenses to attract Canon and Nikon users, at least the ones used to shoot with D850/5D Mark IV cameras and G/L lenses. The f2.8 trinity of Pentax lenses are already 5 years old. In 6 years these lenses will be 11 years old and will have to compete with newer and newer mirrorless lenses...
There are a lot of things that can go wrong or good for Ricoh no matter the path they choose: mirrorless or DSLR. The important thing is to remain in the market and not because of competition but because of photographers having more choices.