As someone who really doesn't think gear plays that large of a role into the quality of the content. I still have been wondering how much better an A7iii will be for stills over a GH5.

I've been a cinematographer for quite a number of years now and have extensive experience with raw video workflows/grading. I use a GH5 for personal travel projects but have been wanting to get into stills. How much will the A7iii benefit me in terms of what is achievable? The dynamic range , FF DOF, and autofocus speed all seems very inciting, but honestly I have no experience with taking stills and what is useful in a stills camera besides the obvious from cinema cameras(dynamic range, ability to recover shadows/highlights in post, etc) I have concerns with my GH5 for some aspects such as portraits, the smaller sensor makes throwing the background out of focus a bit more difficult, and with adapted lenses via a speedbooster, the autofocus is abysmal.