This article certainly hit home for me. I did purchase the R5 C primarily for still photography, but I wanted the ability to explore video. Today, I'd gladly purchase an R5, but didn't years ago for obvious reasons. Things changed with it thanks to several good firmware updates, but I still like that the chances of my camera reaching any type of thermal limit is pretty non-existent as long as I have power, and I do in a solution that fits in a shirt pocket.
The MFS has also remained under utilized. I agree the lack of Wi-Fi support in Cinema mode was and continues to be a bummer. No one ever expected to the ability to transfer video, but the lack of basic camera control was a huge miss on Canon's part. Not to mention the level of support you don't get when using the body with a gimbal. Even connected via USB-C all you can do is start / stop.
Still however, this camera excels in so many areas. No camera is ever perfect. Its absolutely time for a Cinema Series refresh given the C70 is the only dedicated RF mount video camera. I know good things are coming. I'm not likely to upgrade. I like my camera too much and am not video centric enough to warrant a change.