According to a USA Today "Fact Check," the Republican Chairman of the House Committee investigating the J-6 Committee, Congressman Loudermilk of Georgia, "No evidence was destroyed." They cannot find the original copies of a couple of tapes, but transcripts were kept. Transcripts meet the Congress' standards for "evidence."
You had two choices, here, the first choice was to look for factual evidence. The second choice was to repeat lies from the echo chamber that reinforced your prejudices.
Before you dismiss "USA Today," as "Lamestream Media,' it is and was a Conservative newspaper. Back when I worked as Regional Director for Public Affairs the Deputy Secretary was a Conservative Republican Activist named Tom Harvey. When his wife, Kathleen Black, was made Editor of the paper, Harvey told me that it was and would always be Conservative. He never lied to me.