It varies so much depending on your situation.
Will you plan to breast feed? Which nappies will you use? Do you care if the nursery furniture is all matching?!
If you have family that can provide free childcare/general support that makes a huge difference.
We spent about £1200 before dc arrived buying kit for our newborn, much of it second hand (pram, cot, car seat, nursery monitor, nursing chair, lots of clothes and toys, all ebay or Facebook)
We were given lots by friends too, who have had young children and that helps hugely.
Other costs - a hypnobirthing course (worth every penny!), then out of the blue a £350 bill to see a paediatric consultant privately when DC was just 1 month old. (NHS referral was too slow, and my googling told me that DC would likely need an operation before 4 months old. Only way to get referral to specialists at Great Ormond St was to pay for an initial private appointment at our local hospital. It’s terrible that we had to game the NHS system that way, but it was the best £350 we ever spent, she is now hopefully v healthy)
So yeah - the general gist of the more money you can save the better, is about right! But if you’re thrifty you can go far with a lot less 