Hi there,
thats because you’re using the Woocommerce Blocks – for some crazy reason Woocommerce decided to NOT use the same HTML or CSS styles for their blocks as they do in their Templates.
Personally i do not use the Woo Blocks, instead i use the shortcodes:
https://docs.woocommerce.com/document/woocommerce-shortcodes/
These do use the Woo templates and the respect the Customizer settings.
If you must use the Blocks then it requires CSS to change the colors:
.wc-block-grid__product-rating .star-rating span:before, .wc-block-grid__product-rating .wc-block-grid__product-rating__stars span:before {
color: #ff0000 !important;
}