Apart from networking, the hourglass design is common throughout
Electricity is an hourglass. Coal plants, solar panels, gas turbines, wind turbines, nuclear power plants all produce electricity. This is then consumed by electric cars, computers, washing machines, etc.
LLVM IR is an hourglass. Many compilers and languages produce LLVM IR. This is then converted to many different instructions sets.
I think if you want many-to-many non-coupled relationships, you will end up with some sort of hourglass design eventually.
Electricity is an hourglass. Coal plants, solar panels, gas turbines, wind turbines, nuclear power plants all produce electricity. This is then consumed by electric cars, computers, washing machines, etc.
LLVM IR is an hourglass. Many compilers and languages produce LLVM IR. This is then converted to many different instructions sets.
I think if you want many-to-many non-coupled relationships, you will end up with some sort of hourglass design eventually.