Matt Johnson mentioned the  three must-have features he says Sony needs to add:

• Internal RAW Video Recording
  When the A7S III was released, internal RAW video was limited to cinema cameras or external recorders like the Atomos Ninja V .
  Today, cameras like the Nikon Z8 , Z9 , and Panasonic GH already record RAW internally. Matt believes Sony must bring internal ProRes RAW or their own X-OCN codec from cinema cameras like the Sony FX6 and Sony Burano to the A7S IV and FX3 II.
• Open Gate Recording and Anamorphic Support
  Unlike rivals, Sony still crops video to 16:9, wasting sensor area. The Panasonic S1H II and GH7 offer open gate recording, which uses the full sensor and supports anamorphic lenses. Matt urges Sony to allow full 3:2 and 4:3 recording modes, proper de-squeeze previews, and frame markers to attract serious filmmakers.
• Internal 32-Bit Float Audio Recording
  Panasonic and Nikon have moved ahead again with cameras capable of recording pristine 32-bit float audio. Sony already sells high-end microphones like the Sony ECM-B1M , and the technology is there—it just needs to be enabled in-camera. According to Matt, audio is half of any good video, and Sony must match Panasonic’s innovation here.

Conclusion: Sony has long been known for pushing innovation in hybrid video cameras, but the competition has finally caught up. If the next A7S IV and FX3 II want to reclaim Sony’s reputation among filmmakers, internal RAW video, open gate recording, and 32-bit float audio are no longer optional—they’re essential.