The whole scenario with Nagato absorbing B's chakra played out AFTER Nagano was hit. Meaning B didn't lose any speed or power until his lariat hit Nagato. So tell me how did B lose power and speed when his cloak was absorbed after the impact, and based on both you and me thinking B's power comes from his cloak?
The same way Rasengan lost all power behind it
after it slammed into the Deva Path. Because it was absorbed. It being after he got hit doesn't matter. The only difference between these two scenarios as already discussed is that the impact from Nagato's hit wasn't negated as he was still sent flying backwards by the lariat.
-B hits Nagato.
-Preta Path is activated.
-The cloak is absorbed thus it's basically Base B hitting him.
-Ay hits Nagato.
-Preta Path is activated.
-Ay's cloak is absorbed, but Ay's physical power doesn't come from his cloak thus he still gets a hole ripped in his body.
Stop arguing that Preta Path weakens a hit that is mostly physical power and not chakra.