Quick google lead me to this lugen presse fact check. >WHO changes, inauguration are not linked The claim correlating WHO's new guidance with President Joe Biden's inauguration on Jan. 20 also appears unfounded as it is a second iteration of information first appearing on Dec. 7, 2020. https://www.usatoday.com/story/news/factcheck/2021/02/11/fact-check-post-distorts-whos-covid-19-pcr-testing-guidelines/4340677001/ So they changed it after Biden won.

They reduced the PCR cycles for the vaxed before they recommend not testing the vaxed at all.