You might want to do some more research and / or rent one and confirm the lens line-up is not there nor are the controls on the body for exposure adjustments. A high fps number without effective controls to adjust the exposure to changing light is an incomplete implementation. Adapting 3rd party lenses may address missing focal lengths, but is the AF performance the same as the lenses on their native bodies? And be sure to bring a pocket full of batteries if you plan to shoot all day. Sony is pushing the other two and they have resources to wipe them both off the map. But, they may need less of the mass-market approach of the larger corporation within their high-end camera division.

It's a bit off the OP's question, but what controls do you think are missing on the a7rIII body and other than a dedicated 500 or 600 prime, which are coming soon, what lenses are missing?

To the OP's question, AI is dramatically improving what can be done with smaller cellphone sensors and at a very fast pace. They are quickly approaching the quality that can be produced by 1" sensors as well as APS-C sensors. It will be a while before they get anywhere near FF sensors, but the day will come sooner than most think. That doesn't mean they will replace the DSLR as their sensors will also be increasing in size/quality/output through AI....eventually. 😉