They were more worried about Hitler and assuming no WW2 or a buildup towards it, the Anglo French alliance will try and block Italy from what they see as aggressive expansionism.
Which ones? India was ongoing but it was slow and without WW2, it's much likely to come in negotiated manner, Indochina was brewing but there was concerns about the Japanese already and the Algerian and West African ones had root in the chaos of WW2 in France and bad treatment of colonial troops. Without a ww2, France and Britain are much stronger and stable and can keep their colonies for a few decades more before needing to pull out of them.
Who ever said anything about Mussolini being toppled? I simply said that a forever war in Ethiopia that is being supplied by an hostile Anglo-French alliance won't be good for the Italian economy because they can't properly exploit the land when guerrillas keeps disrupting it, meaning Italy will be sinking man and money into a place that is giving them nothing but trouble, combine that with the inefficiency of fascist system and that Italy was no Germany and things are going to look grim for them