Yeah, unfortunately the GH4 was an odd duck. I never owned one, the colors were funky and well it just looked rushed to market to me. I had a G7 I think at the time, and I really liked it too well to give up for a GH4.
The GH5 was a massive improvement, but it took a Long time for it to come out. The GH6 is the same way time wise, but I have not been super impressed with it either, it just seems like most of the people that have it don't publish much about it, just the normal talking heads seem to review it on YouTube, and even then don't get much into how good or bad it is. Odd for sure.