To who? Who are these people who know what the classes are and what their spell lists are, and can flawlessly recognize each spell when it’s cast? Do people in your worlds go around talking about how “Cleric Dan cast Flamestrike on that bandit captain, and the Captain was all, ‘oh crap they’ve got a Cleric y’all that was the Cleric spell Flamestrike we better run!’”?
Also it’s funny that you went from ardently insisting that bards have to make music to cast, and when I showed that isn’t true, you just dodged away with “that’s irrelevant!” Instead of admitting you were wrong about that aspect of the discussion.
Absolutely. And since no one knows what spell list a cleric has, because that sentence is full of mechanical concepts that don’t exactly translate into the game world, and don’t apply to NPCs by default, no one can tell that the Bard is a bard.
Simple fact is, a Bard can orate (Recite psalms) to cast spells, and so can a cleric.
All magic is from the weave in 5e, IIRC, not that that matters at all to the actual topic.