Well the game's development got its own share of hiccups in development. I've been following this game for quite a long time already and I'm surprised they didn't drop this somewhere along the way considering how ambitious this project is. I know a bunch of other RPGM games that get dropped after at most a year of development.
Now we're finally looking at a complete game after 4 full years of development with its own good share of delays and one major overhaul with artist change and so on. Honestly whoever followed this project long enough would remember the huge delays we used to get back then that even at one point there's like zero communication for over a month that people thought they actually abandoned the project.
To be honest I never expected them to finish this but here we are, just a few weeks away from the final version. Only thing I have left to say to them is good luck on their next project and the DLCs.
There's a few things that you mentioned that I think should be set straight.
First one is my personal opinion. Most games I followed sadly either got dropped (most of them in the 1 year period you mentioned) or they kept slowing down to the point of only releasing once a year. There's actually very few exceptions to this. I don't follow all the 3D recycled junk around, though. That's why I see this game in such good light.
Second. They never stopped communicating anywhere near over a month. Maximum amount of time I remember the developers disappearing for was like a week and a half and during that period Ryuuzenmaru was keeping us more or less informed but feel free to take screenshots and quote me if I'm wrong. There was sadly the period where the main developer mom died but the whole story behind the developer's perseverance through adversity is widely known at this point so no point in going over it again.
Third. It's a common misconception, but they never changed artists. They hired an additional one to the one they had already.