Even with better equipment that still doesn't mean the British forces in Egypt wouldn't tear Italian 10th Army to pieces.
It's like giving some third world African militia army Abrams tanks and F-16s. Just because it's top of the line equipment doesn't mean they are giong to be able to win if they take on someone that has equally decent equipment but that also has far superior training.
Another thing to consider. You basically have the Italians doing nothing but building up through June of 1941. Britain isn't going to have as much pressure on them as in OTL, obviously they aren't going to be setting on their asses, picking their noses.
This delay in attacking Egypt by Mussolini will give the British forces in the region time to secure French positions in Syria, and build up more forces, bring in additional divisions and reequip existing units with more and/or better equipment.
Or trying one of the famous 'Churchill' plan as there are no other front.