Unlike the OSI model, most computer systems have fewer layers. Why not decrease layers? What are the drawbacks of using fewer layers?

However, the vast majority of computer systems use fewer levels than the OSI model mandates. Because of the nature of computer systems, this is indeed the case. Why not use fewer layers than you currently do? If we use fewer layers, what possible drawbacks might we encounter?

However, the number of layers recommended by the OSI model is greater than what is typically used in computer systems. Because of the design of computers, this is inevitable. I believe you could benefit from employing fewer layers. I was curious about the potential drawbacks associated with utilising fewer layers.

However, most modern computer systems don't make use of all the levels needed by the OSI model. Why don't we try to get as few layers as possible? Is there anything that could break if fewer layers are used?