This is something you'd learn in your first year at law school. If, as Trump's complaint alleges, Dominion did destroy evidence then the evidence is immediately assumed to support the opposing party's allegations.
Biden's defense would now have to prove there was no fraud as if Trump's team had certain evidence of there being such.
Giving them what they want is not the correct solution. They also want us to do nothing.
I like the Trump method of giving it to them tenfold.