Everest isn't the point on Earth closest to space — an Ecuadorian volcano is

Earth bulges outward at the equator, so a point near the equator starts out farther from the planet's center before any mountain is added. Measured from Earth's core, the summit of Ecuador's Chimborazo sits about 2.4 km farther out than Everest's summit, despite standing over 2,500 metres lower in elevation.

— NOAA National Ocean Service, Which mountain peak is closest to space? — NOAA Ocean Facts