especially if you have kids, your available possessions will swell to fill your new house. If there is a reason kids need separate bedrooms that is a good reason, if you need to change locations because of work or school, that is a good reason, if you can get a larger house on good terms for not much more than your old payment, that is a good reason but it depends on the market. We made a killing buying the last house we owned because we got more floor space and more rooms, bigger lot, for same base price of the house, but cheaper payment but this was for a lot of market reasons.
If you love your location, consider adding on to get space you need, for instance a family room with one small or two large bedrooms above, a dormer bedroom etc.
my brother did a remodel where a garage became a kitchen and family room, and old, small kitchen became utility room, office and dining area. In-laws took a porch-patio, extended it to a much needed family room and dining area, make living room a 3d bedroom, and made dormer a teen bedroom. They did not add a bathroom, now wish they had, but it was the most expensive option.
All the usual caveats on home improvement and contractors apply of course.
A lot of new house construction today seems to us to have a lot of wasted space, cathedral ceilings, great rooms, 2-story front hallways etc. that add to sq. footage but do not add to usable living space. DD bought a house like that. It gave them 2 more bedrooms, but for double the square footage of the small ranch house, not much more actual space, except the basement playroom and workshop.