Yes, Afghanistan is a much better team than Zimbabwe. Even they are so good that they could beat Zimbabwe, West Indies, Bangladesh, Sri Lanka and Pakistan very easily. They may also give a tough time to the big three teams, but sadly I don't see them playing any international series lately. We are witnessing one-sided matches where West Indies and Zimbabwe are losing matches without making any efforts, and this decreases the viewers' interest when they already know who is going to win.
People will be more interested in watching matches between Afghanistan and Ireland compared to matches between New Zealand vs Zimbabwe or Australia vs West Indies.
Afghanistan deserves a few matches against teams like Australia and New Zealand. But I believe that some of the SENA boards want to expel Afghanistan from international cricket and that complicates things. Even associate nations such as Scotland, Netherlands and Nepal are now performing better than Zimbabwe. And that too with 1/50th of the funding that Zimbabwe receive. But the ICC remains blind to this and they continue to prop up Zimbabwe by pumping tens of millions of USD into that country every year.