Why could only rock and metal solidify near the early, hot Sun?

Volatile materials could not condense due to the intense heat.

The initial ignition of the Sun created an extremely hot environment in the inner Solar System. This high thermal energy meant that substances with low melting points, known as volatiles, such as water ice, methane, and ammonia, remained in a gaseous state and could not condense or solidify into planetary building blocks. Only materials possessing very high melting points, classified as refractory materials like rock and metal, were capable of solidifying under these scorching conditions. This temperature gradient created an effective sorting mechanism, leading to the formation of dense, rocky cores closer to the star and the accumulation of lighter, icy materials farther out in the cooler regions.