BT cuts back on G.fast speeds, deployment. 150-400 down is still a big improvement over BT's current network but it will typically be half the speed originally planned. BT was going to deliver 500-800 megabit G.fast to most of 4,000,000 distribution points on light poles, in basements and in very small dug in enclosures.
Instead, they would deploy to existing cabinets (10,000's of thousands,) avoiding the cost of running fiber so many places. That saves billions but reduces typical download speed from 400-700 megabits to 150-400 megabits. In either case, 5-15% or so of homes will run even slower.