I replied someone who asked why was Shakyamuni Buddha depicted with hair unlike other monks:

My dharma friend Kyle Dixon said before, “Attributes like the curly hair, and elongated earlobes etc., are part of the major and minor marks of the Buddha’s sambhogakāya form.”, “The major and minor marks are the sambhogakaya. They are not visible to normal afflicted sentient beings.”

This sambhogakāya is only perceivable by awakened beings at the eighth bhumi and above.

Hence I tend to believe Birk McClain that Shakyamuni Buddha was visually indistinguishable from other monks (that is, bald) for ordinary people. 

In fact, some people could not tell that they met the Buddha. 

For example:

MN 140, the Dhātuvibhaṅga Sutta, opens with the Buddha staying overnight at a potter’s workshop where he encounters the monk Pukkusāti—a renunciate who had been searching for the Buddha based solely on renowned reports of his wisdom. Despite his earnest quest, Pukkusāti admits that he has never seen the Buddha and that even if he did, he would not be able to recognize him. This irony highlights the gap between the reputation of the Teacher and the actual, unassuming presence of the awakened one.

When the Buddha inquires about Pukkusāti’s spiritual motivation and his teacher, the monk reverently describes the famed Gotama—the Blessed One—whom he reveres yet has never personally encountered. It is at this moment, upon realizing that Pukkusāti’s renunciation is driven by an abstract faith rather than direct experience, that the Buddha decides to reveal the essence of his teaching. Rather than making a dramatic declaration like “I am the Buddha,” he subtly discloses his identity by commencing a profound exposition on the nature of existence.

In his discourse, the Buddha explains that a person is constituted by six elements, six sense-domains, eighteen mental explorations, and four resolutions. This detailed analysis shows how understanding these components—and recognizing them as impermanent and not-self—leads to detachment and liberation. Thus, through the act of teaching, the Buddha indirectly reveals his true identity as the enlightened one, guiding Pukkusāti (and listeners) toward the realization that true insight arises not from external accolades but from direct experiential understanding of the nature of reality.