Can you elaborate though? Is it better (and for what reason), to run Electrum Server upon your node, instead of connecting Sparrow to your node?
No, it's no better or worse. In both cases, all your data will come from your own node rather than that of a third party, and so your privacy will be maintained. If you already have an Electrum server set up, then no reason not to use it.
There are actually too many people that used to use Electrum since it was released and haven't switched to any other alternative. That's what made me curious.
If you are already familiar with Electrum and already have a server set up, then I see no reason to change unless you wanted to use Whirlpool.