Unless all of the housing is owned by non-residents prior to gentrification, some residents always benefit from their neighborhood going upscale. Either through increased home values, allowing them to sell and improve their lives. Or because it's now a more pleasant area to live in.

Even renters in gentrifying areas may profit if housing construction outpaces population growth. Yes, they may have to move, but also the places they move to on their current budget may be nicer - because the people who can afford better have moved too.

> increased home values, allowing them to sell and improve their lives

That also raises property taxes, making the neighborhood unaffordable and driving them out.

> it's now a more pleasant area to live in.

For new wealthy residents. People who have spent lifetimes there don't want everything to change and have their communities destroyed.

> Yes, they may have to move, but also the places they move to on their current budget may be nicer - because the people who can afford better have moved too.

These are theoretical and very general averages. The actual individuals often do not benefit. Being forced to move is not a mere inconvenience to your theory.

When people in NYC are driven out of their neighborhoods because of gentrification, they generally move down south. There isn’t some magical part of town that they can afford with their “current budget”