Though I would have liked to have seen Donavan Brazier and Paul Chelimo racing in the finals, I don’t feel that I can really complain about those DQs. They and several others broke the rules and the officials enforced those rules. Per Colleen Quigley’s comments, it may have been more challenging to stay on the track with the steeply banked curves, so, I think that athletes should have had access to the track prior ot race day to familiarize themselves with track conditions. As for Farah, perhaps he should have been DQd. It does suck though when outcomes are decided by officiating.
Perhaps instead of a DQ, they could assess a penalty in the results. The simplest method would be to asses a fraction of a second penalty and then adjust their finish time and place by that amount and disallow that performance for any record consideration. They could also assess a distance penalty (maybe 1m? how much advantage could really be gained with 1 step?) and apply it using finish line photos. A distance penalty would scale better across different running velocities.
I also thought that athletes could maybe have one free step inside during each race, but then I imagined everyone taking a step inside as they come out of the final turn and that seems ridiculous.