The AV1300 rating is plain bullshit - the QCA7550 still adheres to the AV1200 standard, which happens to go a bit above 1200 Mbit in perfect (read: laboratory) conditions.

Sounds like you're confusing things. You probably have 2.4 and 5 GHz wireless channels from your internet router - and that is nothing to do with the wired connection your PLC kit should be on.

Don't, for this will cut PLC bandwidth straight in half. The actual issue is poor electrical filtering in the affected equipment's power supply circuitry. To solve this, put these devices on a...

Seriously? That's about as nonsensical as advice can possibly get. Factory-reset the adapter first, then update, then pair it back into your network - without disabling any vital functions in it.

So long as the protocol between the modem and the router is an IP protocol, I see no issues. Powerline adapters should be completely transparent to the communication between modem and router. What...

That is true - it is a shared media network, so just like with WLAN, you can expect payload throughput to be about 1/2 to 1/3 the physical media bandwidth. tpPLC utility shows the latter. 8030P V1...