Sony RX10 iv or Nikon D800 - switching back?

I switched to the Sony RX10 iv two years ago. Is it time to go back to Nikon? After two years of shooting with a one inch sensor, I miss the image quality and low-light capability of a full frame camera. What should I do?

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IT/Photo Equipment:
Apple iPhone 11 Max Plus
Phone battery 22,400 mAh
Phone charger cable
iPhone App - View Ranger
iPhone App - PhotoPills
iPhone App - Polar Scope Align Pro (Complete Kit)
Earphones
Rode Wireless Videomic Go
Sony RX10 iv camera
Nikon D700 with Tokina AT-X Pro 20-35mm f/2.8 lens
GoPro Hero 7 Black plus accessories
BlackRapid camera strap
Think Tank Camera Utility Belt and pouches
Manfrotto 190CXPRO4 carbon fibre Tripod
Manfrotto MH054M0-Q2 Tripod Ball-Head
Black Diamond Revolt 350 Headlamp
Aputure AL-H198C LED Lamp
Lee Filters filter system
Lee Filters Circular Polariser
Remote shutter release

AAA Batteries - spares x 6
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Lens wipes and brush
Spare SD cards