I agree that comparing Bitcoin and PayPal makes no sense due to their nature and usage. But it's ridiculous to say this
People are using this platform to pay for a wide variety of things, whereas Bitcoin is not a payment tool, even on the best of days. As such, the annual transaction volume is incredibly misleading when taking it out of context completely.
Bitcoin usage as currency or payment method isn't as low as people think, because it's legal in few country & there's small group who use Bitcoin to pay goods.
well it's impossible to know the reason for every Bitcoin payment, whereas PayPal literally do have a recorded reason for every transaction (although some unknown amount of that will be deliberate misreporting)
it's worse with LN payment channels, as only the sender and the receiver really know about the transaction and what it was for, the route the money takes between them is obscured even to those relaying along the route (and that's a deliberate privacy feature). Eavesdropping on every network-wide change in channel balance won't work either, as any private channels moving money through the network screw up that kind of analysis.