Complex sentence: Initially, Sega proposed the universal adoption of its own system, but after objections by Nintendo and others, Sega took a role in forming a new system that would become the Entertainment Software Ratings Board, an independent organization that received praise from Lieberman.
Split into simpler sentences: Initially, Sega proposed the universal adoption of its own system, but after objections by Nintendo and others, Sega took a role in forming a new system. This became the Entertainment Software Ratings Board, an independent organization that received praise from Lieberman.