What do you mean ? .. over 80 percent of nodes run core .. trust is everywhere :-)
Discussion
If you audit core, or knots, or btcd, or your own fork, etc., then it's trustless. The option is there always.
If you don't run a node, it's completely moot.
What percentage of node runners even read code ? Wild guess ?
Of the ~23k who are capable of opening ports...I'd estimate 10%.
20% of those can probably audit core capably for their own purposes.
0.1% of those I think ever do.
Conversely, of the folks who don't run nodes, the math is easy. 0% of them can ever audit what they use.