more so than和unless done的问题

2 more so than和unless done的问题

1. A survey by Barna research group found the top reason given by Americans for the fake news phenomenon is “reader error”，more so than made- up stories or factual mistakes in reporting.

问题1: 请教曹老师，这个more so than 我不会分析，看不懂这是个啥用法,,

2. Merely helping a gift-giver gain access to other officials, unless done with clear intent to pressure those officials, is not corruption , the justices found.

问题2: 请教老师，这个unless 后面省略了it has been 吗？it指代前面那个动名词短语。