What should my MSFS-2020/2024 settings be?

Required : Turning Off all of the in-game ATC options

MSFS 2020 

Under Options menu :

• Assistance Options, Piloting, AI Radio Communications (ATC) - Off
• Assistance Options, User Experience, ATC UI Panel - Off
• Assistance Options, User Experience, ATC Enforce Flight Plan - Off
• Assistance Options, User Experience, ATC Voices - Off

MSFS 2024
(Updated for SU3)

Settings → General → Sound

• Set Character Voices slider → 0

Settings → Assistance → Realism

• AI Radio Communications (ATC) → set to Off

• ATC Enforce Flight Plan → set to Off

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Recommended : Turning Off MSFS built-in traffic for SkyNet and AI Living World

* SkyNet : SayIntentions.AI Multiplayer Network

* AI Living World : SayIntentions.AI Traffic Injection (AI aircrafts)

MSFS 2020

Under Options menu :

• General Options, Data, Data Connection, Live Real-World Air Traffic - Off
  
• General Options, Data, Data Connection, Multiplayer - Off
• General Options, Traffic, Aviation Traffic, Aircraft Traffic Type - Off
• General Options, Traffic, Airport Life, Ground Aircraft Density - Off (0)

MSFS 2024

(Updated for SU3) 

Settings → General → Graphics → Global Rendering Quality

• Scroll down to Parked Aircraft Quantity → set to Off

• Scroll down to Aircraft Traffic Quantity → set to Off

Settings → General → Online

• Aircraft Traffic Type → set to Off

• Air Traffic in Career → set to Off

For VR:

• Settings → VR → VR Graphics

• Scroll down to Parked Aircraft Quantity → set to Off

• Scroll down to Aircraft Traffic Quantity → set to Off

Reminder

You also need to remove/disable ANY other add-ons that may be injecting traffic into the sim.

Don't forget to do the same for VR Graphics settings (VR, VR Graphics) if you're a VR user !