If you pour water into one end of a swimming pool, it raises the water across the entire pool. Water always seeks a level surface.

The same thing is true with the oceans. If glacial melt was accelerating, then we see acceleration in sea level rise rates at every tide gauge on the planet. All of the oceans are interconnected.
If glacial melt was accelerating, we would see an upwards curvature in tide gauge data, like this.

But we don’t. Tide gauges show no acceleration.

Tide gauges on the East Coast show no upwards curvature (acceleration)

Tide gauges in Northern Europe show no acceleration. Sea level is falling there

Tide gauges on the west coast show no change in sea level at all

People who claim that glacial melt is accelerating, are lying. If it was happening, upwards curvature would be visible at every tide gauge on the planet. We don’t see that.