I’ve gone from 70mm stem with 690mm bars, to 760mm bars (intending to cut them down a touch tho, when I get round to it). Like trailflow, I didn’t feel much difference to the steering, not in the way you’re suggesting anyway, like you do when dramatically lengthening/shortening stems.
Apart from the obvious arms being wider apart, the main difference I found:
slightly improved balance in a straight line and cornering
had to relearn hoofing the bike up steps and large obsticals/step ups, arms being wider apart is a less efficient action, so more effort required pulling up hard on the bars to get the bike up a big step up..
Personally, unless you’re a big bloke with massive shoulders, 690mm-710mm is better IMO.