I did not use discord extensively but when we tried, in short, one could upload stuff but not easily retrieve them. I suppose they will fix this one day, but the lock in (read: the amount of data uploaded) to telegram will be stronger and stronger.
telegram, although with more "effort obstacles" than discord, has also a lot of clients.
So let me take a screenshot to show you.
In short: the telegram chat is quite full of talks and multimedia already, moving is possible but would lose this data. Then again, I don't get why a discord link should expire. I do not know who can create those.
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