"It takes your typical script kiddie neighbour what.. 3 weeks to brute force a SKY or TalkTalk router compared to modern BT router taking significantly longer."
Assuming the wifi uses preshared keys and the person trying is determined, the differences between hacking them is tiny if it is actively being used:
https://gbhackers.com/crack-wifi-network-passwords/
While BT saying "our wifi passwords aren't as weak as our competitors" is an option, I'm not sure it's a claim you want to advertise.