The simulator related files used to be there until around Xcode 6. If you've been using this machine for some years, it may be worth looking for ~/Library/Application Support/iPhone Simulator.The Caches folder may grow over time as well, and you can remove contents from there, and they should be regenerated as needed. If you no longer need to run your apps on certain devices, you may consider removing those devices' corresponding folders in the Devices folder. It includes a Caches folder and a Devices folder. ~/Library/Developer/CoreSimulator/ contains simulator related data.Thankfully, it is organized by date, so you can choose to keep specific folders inside it, and delete the rest ~/Library/Developer/Xcode/Archives/ contains data from your builds that can be helpful in the process of symbolicating/debugging deployed apps, but could otherwise be removed.If the objective is to free up disk space occupied by Xcode-related and simulator-related caches and data, and not just iOS support files, there are other folders you can look into to consider removing files, besides ~/Library/Developer/Xcode/iOS DeviceSupport/ and ~/Library/Developer/Xcode/DerivedData that have been mentioned in the other 2 answers so far.
