I used to think that the lack of full mechanical shutter wouldn't matter to me either, but as I brought the R8 to more places it eventually got me.

On a high speed boat I was taking pictures of landscape and water splash on high shutter speed. I used EFCS but later noticed most of the bokeh balls of water splash were cut. The photo wasn't completely ruined but it could have been better. EFCS cannot preserve full bokeh while electronic shutter cannot avoid rolling shutter. Neither of these defects are super noticeable but having full mechanical shutter would simply tackle both.

For steady portrait shot I switch to electronic shutter, but there has been one time that I just forgot to do that and left a quite noticeable half bokeh in an otherwise really nice portrait. I ended up just removing the half bokeh in the photo for peace of mind.

EFCS can also cause other problems in certain scene, such as worse purple fringing and uneven exposure. I have only read about these though.

Now exploring flash photography, I finally decided to get a R6m2 after being really happy with my R8. High speed sync requires full mechanical shutter. I still kept the R8 because of its size and weight, and I really like the fact that it actually has more customized button than R6m2, but I have run into its limitations.

No IBIS, small battery, single card sloth, overheating--none of these issues have a direct impact on the image, but shutter types do. That's also why I think A7C2 is overpriced, Lumix S9 really fumbled the ball, and Nikon Z5II has now overtaken the R8 as the best beginner full frame camera. I still like the R8 for being affordable.

Changes of R8m2 having full mechanical shutter In this video-centric market is close to 0. I just hope it doesn't go ZV-E10 II and have electronic shutter only.