By meek and unimpressive you mean they actually sound like a radio should on AM instead of a pile of overmodulated overdriven bassy unintelligible crud.
People on CB have been doing crap overdriven unintelligible audio on AM so long they think its how it should sound. Err, no.
I don't know why the video shows the hard way of doing things. It isn't necessary to use the ACC plug if you have the right mixer.
I use a Yamaha MG 10 small format mixer with 3 band EQ that has balanced XLR main outputs. I use a Heil XLR to 8 pin cable with the PTT pigtail jack wired for my Kenwood TS590 and plug straight to the mic input of the radio from the XLR output of the mixer.
not to mention a certain actual Amateur only dedicated website,....... he gets HAMMERED on there