"we were just encouraging them to tell the truth"
I doubt there will be any criminal upshot for attempting to interfere with a congressional investigation, but it doing so does add to the perception of corruption and criminality around the former president. A lot of today's testimony tends to establish state of mind and intent. Even if no criminal charges are brought, the image of Trump scheming until the last to cling to power and siccing a violent mob on the US Capitol to derail certification will be hard to dispel.
Details like Trump's lunch tantrum or trying to choke Engle, dramatic as they are, aren't so significant as the cabinet level discussions of invoking the 25th.