On 20w09a, piglins will barter warped nylium, and you can turn into them to netherrack, making renewable.
But on 20w10a, piglins no longer barter this, and making no longer renewable.
https://bugs.mojang.com/browse/MC-173237?focusedCommentId=641766&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-641766
https://bugs.mojang.com/browse/MC-173237?focusedCommentId=641497&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-641497