31" & 32" pitch was common. Not 29" in my experience.
The thickness of the seat backs has reduced in recent years.
Narrower refers to width.

Seat pitch is a poor measurement to determine space. The distance from the seat back to the back of the seat ahead at knee height is a more accurate & useful measure.
Seat width is also sometimes given and another poor measurement. Seat to the adjoining seat pitch is better as it gives a more accurate measure of shoulder to shoulder space.

https://en.wikipedia.org/wiki/Airline_seat