On Telegram It's just very fast to create a bot and getting started. I've tried WhatsApp before but too complicated and Signal was also complex. I'd say that Telegram was the easiest to get a poc working.

Did you consider Zulip? I've always wondered why Zulip isn't used more often by communities. Seems like it could be a great hybrid between Discord and Telegram.

Frankly telegram is the easiest to integrate with bots… I know, I’ve been down the same rabbit hole