Scripture reserves religious worship for God, while human beings can also receive gestures of homage in non-divine settings.
Exodus 20:3-5; Deuteronomy 6:13 provide the worship background.
Within John, the man's understanding of Jesus rises progressively until he believes and prostrates himself before Jesus, who accepts the response.
The accepted worship/homage is strong cumulative evidence when read within a Gospel that has already identified Jesus as God.
The healed man says, 'Lord, I believe,' and worships Jesus.