Boys, after hours of trying to figure out why my Videos looked so washed out after i exported from Davinci, i've finally found the one thing that was making the difference. This one Setting is extremely important: Go to DaVinci Resolve → Preferences → General → Enable “Use Mac Display Color Profiles for Viewers.” → Restart Resolve.
This will make sure that what you see on your Davinci preview, corresponds to what iphone users will see on instagram, tiktok etc.