I’ll take an opposite opinion, or at least temper it with “it depends.” When my kids were 2.5 they could sit in their seats and their legs would stick out straight and not come anywhere close to the seat in front of them. It was when they were older (4ish) when their legs could actually reach the seat in front that I’d worry about kicking.

If your kid’s legs can’t reach the seat in front, then pick whatever seat is most comfortable for you. I hate most bulkheads as i like to stretch my legs out under seat in front of me, plus bulkhead seats often have trays in armrests which take away from width. When travelling with a kid you can also raise movable armrests in other rows and take over some of their space without concern.

If seat kicking is a concern, either my wife or I or other child would take the seat in front of the child we were worried about, but our concerns never materialized.