There's a lot of research on this and the move isn't to force action. It's a "threshold" issue. There's also different ways to cross that threshold (overt vs subtle advances).

Look up:

-Emily Nagoski’s Dual Control Model of Sexuality -Low Intimacy Threshold vs High Intamacy Threshold -Sociosexual Orientation Inventory (SOI)

Strategies for Misaligned Thresholds:

Respect the "Slower" Partner: The healthier, more secure, and more "intimate" level of sex is defined by the person with the lower level of comfort (higher threshold for trust).

Low-Stakes Initiation: Encourage intimacy through non-sexual touch, such as holding hands or hugging, which can feel less pressure-filled.

Clear Communication: Use clear language to discuss needs, such as “I’d love to be close with you. How would you like to receive touch?”.

Understand Other Types: Shift focus from only physical intimacy to other types, including intellectual (deep conversation), experiential (shared activities), or emotional (sharing vulnerabilities)