This is a reasonable request, but I don't really want to write a code example, that feels like a lot of work and I have 0 investment in changing anyone's mind about this (I didn't really expect this to be controversial - I was just sharing my experiences and expanding on Avlin67's comment about "generic hell"), but if you had a question I'd be happy to answer it.
The only example I can think of is the bifurcation non-generic collections vs. generic collections in the early days of C# when you had a non-generic collection and couldn't pass it to a method which expects a generic collection, but it was the consequence of the development history of C# and is not a problem of generics per se.