The scars of the leaked transcript of President Trump’s conversation with Mexico in 2017 — in which he told the Mexican president he didn’t actually care if Mexico paid for the wall, his signature campaign promise — have lingered far longer than that news story’s shelf life.
So, basically, transcripts (instead of recordings) are made of the calls so the administration can leave out, and avoid creating a record of, anything embarrassing or illegal that Trump says. And they are restricted to a small number of advisers to prevent it leaking when he does.