#4 The old Championship was getting stale
Before you angrily respond to this by saying that the old Intercontinental Championship was the most beautiful one of them all, we're on the same boat. We completely agree with the nostalgia factor being the best but Jim Ross said in an interview that WWE, as old as they are, is a company that's constantly trying to get younger, not older.
WWE always tries its best to stay relevant and modern, which is not a bad thing at all. This may involve steps such as removing the number from "WrestleMania" to not make it sound old and other things that we may not necessarily agree with.
But in this case, there may be some sense to WWE's decision if this is one of the reasons. WWE wants to stay young and cut ties with a lot of the older aspects. When looking at the Intercontinental Championship that was introduced 5 years ago, it's a throwback to the old, great design that we all know and love.
However, it can get old and - sometimes - stale, which is why WWE is somewhat justified in changing the design to a newer one.