Even if the limits are raised, the rules will still not permit them
to
interfere with licensed services such as commercial broadcasting and
amateur
radio even if their emissions are within limits. They would have to
change
that provision also.

I don't think you have a grasp of the problem. Consider the current
part 15
rules that are completely ignored by the manufacturers of cheap
electronics.
They just sell cheap junk and let us fight with our neighbors about
interference or RFI.
How many new hams do you know that have quit HF because of RFI
problems
with cheap telephones and other electronics?
The BPL providers will just push the problem off to their customers
and let
us fight with our neighbors. When they are forced to act, they'll find
ways
to stall and avoid fixing the problems as long as possible (just like
they
do with leaky insulators and bad grounds). Most hams will become
discouraged
and give-up on HF.

Imagine this scenario: Your neighbor gets a shiny new BPL internet
connection
and is dazzled by it's performance. You have serious interference from
his
connection. You complain. The Power Company contacts your neighbor and
says
'we're disconnecting you (and all your neighbors) because the HAM next
door
doesn't like the noise your internet connection makes on his radio'.
Guess who ends up the bad guy.
Steve