You will need to create a new account, but it is possible to export all of your subscriptions to a new account. There should be a thing you can click for that in your settings menu to download the export file, which you would then import into your new account.
Your old comments will not transfer, however.
XMPP would be the best choice at this point in time, as it doesn’t suffer the downfalls of Matrix (though even Matrix would be better than Discord).