What Discord solves well
Community. Separate channels per sport, threads per match, roles for paying members, and bots that keep the group's results table. If what you want is to discuss plays with other people and leave a record, it is the best place for it.
What Telegram solves better
Urgency. A Telegram notification lands on the phone and gets read on the spot; a Discord message gets lost between channels unless you have the app open. For an alert that is worth two minutes, that difference decides whether the alert is useful at all.

The Discord bots worth having
The tracking ones: they log every bet the group makes, calculate cumulative performance and put an end to arguing from memory about who called what. Also the data ones, which pull statistics on request inside the channel.
The ones that are not
The ones promising guaranteed signals and the ones demanding you register with a bookmaker through their link. It is the same pattern as on any platform: when the business is your sign-up, the quality of the alert stops mattering.
The risk specific to communities
Peer pressure. On an active server people bet more than they planned because everybody is on the same match. The shared table helps discipline, but the live chat pushes the other way: decide your stake before you walk in.
Our choice
Our alerts and predictions go out on Telegram, because the value is in arriving on time. Corners bot for the corner alerts, and Best Tipsters VIP for the daily predictions.