To be clear, this has already been a requirement in the UK as a whole for any new or modified construction for quite a while. This new regulation mandates installing a similar system in existing homes.
seems like a good way to introduce additional failure modes, hopefully the law also mandates that the alarms be made in such a fashion that the individual alarm will function regardless of whether the "smart" part of it is getting hit with 200 kV over the wire, or if the smart part is wireless but the radio crashes due to.. I don't know.. overheating issues?
Feels like an over-reaction to me, especially in response to a disaster that killed "only" seventy people, or a third of a day's UK COVID deaths.