Bots? It's awkward. In Slack, you scroll up. No bot is going to be as simple to use and obvious as that. If you do manage to integrate it that well, you will need to set up the bot, which is a separate service, get your clients to understand the bot, etc... It's like suggesting a tin can with strings to solve a communication problem. A rough, imperfect solution.

Who gives a damn about innovative? It may have been obvious and simple, but if no one else is doing it well, and they do, sneering at it seems dumb. They made a good call, and are profiting from it.