Blizzard swore off local multiplayer after what happened with StarCraft esports. The Korean leagues ran huge tournaments and made a ton of money off Blizzard’s IP and essentially told them to pound sand. Now everything has to go through their servers so they control the ecosystem.
Same with how Blizzard now owns every custom game you make. They learned their lesson with DOTA/LOL and feel like all that money should be theirs.
All of which seems to indicate that this is a real problem. People can play Brood War forever, but what happens when the SC2 servers go down?