I think you might be partly missing the point.
1) If Sony put a modern sensor in one of these things, it would have the same spec as a modern camera because it would BE a modern camera. There are a shit-ton of smartphone sensors that have excellent specs that are in the right size range.
2) When compared to a modern mirrorless camera and a superzoom lens and a gimbal, it would be positively tiny by comparison.
Also, camcorders often have completely internal mechanisms (zoom and focus) potentially making them much easier to weather-seal. The benefits in terms of being less fragile in your bag etc might also be welcome.
Also, also, for amateur use, a camcorder looks FAAAAAAAAR less threatening in public than a MILC and large lens... let alone when you add the gimbal. Put an A6700 with superzoom on an RS3 or Crane and you may as well have activated a homing beacon for all private security, toxic law enforcement, Karen's, etc to come out of the woodwork and hassle you. If you're holding something the shape of a camcorder, the fact that it's larger might even make you look less of a threat because buying a big camcorder might make you look a bit silly - the opposite look of a professional setup.