In late September 2019, I wrote to Ford Technical over this very matter. We had visitors and I increased the tyre pressures as per book for 4 adults. Not only did it handle like a pig it was extremely uncomfortable. Even with the recommended pressures for 2 persons I found it a little harsh.
Their reply was: 30lb Front and 30lbs Rear. up to 3 Adults. Full load 35lbs Front and 40lbs Rear. Quite honestly I will leave them as per normal if I carry 4 adults.
I have run the car with these pressures since then and quite honestly I have not noticed any peculiar wear occuring.
The ride is certainly an improvement. They did add that 'We are investigating internally as the owners handbook appears to be incorrect'
Our Ecosport is a Titanium Auto with the 1 litre engine but I should think it would apply to your vehicle too.
Its worth a try, after all it is a cheap fix if it helps, as Colin says start messing around with suspension and one is heading for problems. After all they only put stiffer suspension on a vehicle to make it go around a race track quicker.