- The FBI was investigating Trump at the same time they were investigating Clinton, but kept silent about it while making her investigation widely known. Trump later committed criminal obstruction of justice into that investigation and was let off the hook due to his immunity as President.
- Trump's campaign manager was handing internal campaign data to Russian operatives, the very same ones who hacked her campaign, and lied about it.
- Trump committed criminal campaign finance violations in the run up to the 2016 election for which his attorney was convicted and sentenced to 3 years in prison, but for which Trump himself wasn't due to his immunity as President.
So yeah, maybe she has a right to say "There was a widespread understanding that this election [in 2016] was not on the level".
Clinton withdrew her acceptance of the 2016 election results <https://news.yahoo.com/hillary-clinton-maintains-2016-electi...>.