What is the most accurate opinion regarding the issue of excusing a small barrier underneath the nail?

A small barrier under the fingernail, if it does not prevent water from reaching the skin, then it causes no harm. But if it does prevent water from reaching the skin, then it is pardoned by many scholars, and ablution performed with it is valid. This is the view preferred by Imam Al-Ghazali, Ibn Taymiyyah, and some Maliki scholars.