Unity will serialize changes to scriptable objects to disk in edit mode. To avoid this, you need to instantiate objects, but only in edit mode. This script automates this process efficiently, and with minimal API overhead.

AutoInstantiate.cs

using System.Collections.Generic;
using UnityEngine;

[System.Serializable]
public abstract class AutoInstantiate<T> where T : Object
{
	[SerializeField]
	private T data;

#if UNITY_EDITOR
	private static Dictionary<T, T> instantiatedVersions = new Dictionary<T, T>();
	private T instantiated;
#endif

	public T value
	{
		get
		{
			return this;
		}
	}

	public static implicit operator T(AutoInstantiate<T> source)
	{
#if UNITY_EDITOR
		if (source.instantiated)
		{
			return source.instantiated;
		}
		T cached;
		if (!instantiatedVersions.TryGetValue(source.data, out cached))
		{
			cached = instantiatedVersions[source.data] = Object.Instantiate<T>(source.data);
		}
		return source.instantiated = cached;
#else
		return source.data;
#endif
	}
}

AutoInstantiateTest.cs

using UnityEngine;

public class AutoInstantiateTest : MonoBehaviour {
	public AutoSharedFloat autoVersion;

	void Start ()
	{
		DoSomething(autoVersion);
	}

	private void DoSomething(SharedFloat sharedVersion) {}
}

SharedFloat.cs

using UnityEngine;

// Example usage:
[CreateAssetMenu]
public class SharedFloat : ScriptableObject
{
	public float data;
}

// This class is required to get the inspector to draw
[System.Serializable]
public class AutoSharedFloat : AutoInstantiate<SharedFloat>{}