I went through a similar exercise a while ago and ended up with the earlier RX100 III. This was something like 1/3 the price of the latest model. Have you considered this one? It has the 24-70mm equivalent lens, which might not be enough for you though. It also lacks the magic AF tracking and high frame rates.
I was only considering pocketable cameras, and the main competition was the Canon G5X II. That camera looked better in many ways but I found some raw samples online and they had a few issues. At wideangle, the lens doesn’t cover the whole sensor. Not a fundamental problem but interesting to know. There are also pretty bad CAs in the corners that are inconvenient to deal with, at least in darktable (darktable - correcting blue/purple fringing (drawn mask in style or preset?)). Raw images from the Sony (how “raw” they really are, I have no idea) are much better behaved.
The RX100 viewfinder is OK, but not great. It’s a bit fiddly to use and not very bright or high-resolution. I normally don’t bother with it as the back LCD is bright enough to use on sunny days. I don’t agree that the RX100 (at least the earlier versions) is fragile generally, but the viewfinder certainly feels fragile. If you’re strictly a viewfinder user then the RX100 III is probably not a good fit.
I agree with other comments about the poor UI and tactility. It doesn’t bother as much as I though it might because, shooting raw, usually I’m only changing exposure compensation at most. Prior to the Sony I had an LX100. This is far better in terms of ergonomics, but it just doesn’t fit in my pocket. For me at least that puts it in the same category as an interchangeable lens camera.