Alas, the OP has a very very very good point.

They may specialize in one particular role, but they are still efficient and competent in the rest of them.

People only tell you to learn multiple roles so they can force support down your throat.

And what happens when you have to play a different role? You are clueless and useless.

problem is they are pros and thats their job. solo q is really different

I say know how to play all the roles effectively, BUT only master 1 role.

You should know how to play all roles properly , but you should have 2 roles that you are very good at . Those 2 roles will guarantee your team a victory.

ITT: OP doesn't realize most pros can play all roles. TSMs support plays a very mean ap mid

Actually, they only play a specialized role for the sake of competitive plays. You don't know anything, just stop talking.