I've been wondering when someone else would finally see the problem with using a "standard configuration" multirotor as an inspection rig. The typical under slung camera and gimbal, whether of standard or ball turret design, is by design limited to a very low upwards viewing angle. The motor booms of the airframe of a small hex do not have enough angular separation to keep them out of the image. To overcome those you need to have a top mounted camera option, which makes the system more expensive and complicated for some users. The Alta is an example of such a rig, although designed for cinema work it is also a superb inspecting tool.
A very easy solution for any company serious about targeting the inspection field is to employ frames in X8-,Y6, and H6 or H8 configurations. All of them allow easy installation of a front mounted gimbal with +90* to -90* tilt rotation. There simply is no need for camera pan control as a good flight controller provides extremely smooth yaw. The users have to develop better stick skills but that's a lot less difficult and far less expensive that incorporating upper and lower camera mounts. Some examples of such set ups are found with the old SteadiDrone quads and X-8's and AscTec Falcon 8, which has been renamed to something I don't recall. The H configurations are quite easy to set up, reducing cost and complexity associated with design and production. Incorporating a zoom feature or lens interchangeability are other extremely important features for an inspection rig. An alternative to those is present in the 520 with camera swapping.
Someone serious about developing inspection tools would dispense with trying to capture a piece of the You Tube video crowd. That would of course reduce the number of units sold but such a move would demonstrate the seriousness of company intent for the people and firms that need a true inspection rig. Taking things a step further, the addition of a small FPV type camera at the top of the airframe having 180* of pan capability would allow users a second view that could be used to establish obstruction clearance as an inspection rig transitioned tight spaces.
You don't need to sell a million units to make money, you just need to design a unit that would effectively serve a fairly wide market well enough to charge prices that customers would pay. You also need to put some legwork into marketing to those that would make use of the end product. This is something DJI has done quite well by taking their product to the intended customers in demonstrations. You just can't have the attitude of "If we make it they will come". What's interesting is the price of a camera equipped 520 falls well within the range of what a "starter" inspection rig would cost when standard production methods are employed. Better still, the cost of production would likely be lower than the 520's. Commercial applications require equipment be of a design fairly specific to the application. We cannot expect any single design to be good at all things as a general configuration has to trade off capability in one or more areas to better include other areas. This is exactly what has been done with the 520 and other "standard" configuration multirotors targeting the commercial market. I'll propose it's done this way because it's what people are used to and that designers might be limited in imagination, or that too little attention is being devoted to establishing market demographics.