Email is tolerable because gmail and others implemented software spam filters. Gmail did so because they were in competition with other email providers and it was a way to get users. The incumbent phone carriers have no incentive to compete here.
Other platforms did better solving the spam problem, so most people simply don't use SMS/MMS anymore. The kids and young adults all moved to Telegram, Discord, Whatsapp, iMessage, etc.
Email is tolerable because gmail and others implemented software spam filters. Gmail did so because they were in competition with other email providers and it was a way to get users. The incumbent phone carriers have no incentive to compete here.
Other platforms did better solving the spam problem, so most people simply don't use SMS/MMS anymore. The kids and young adults all moved to Telegram, Discord, Whatsapp, iMessage, etc.