These are just tough situations. Stating the obvious.
Let's just look at Hull. As she comes off the turn she does push out more to the outside of lane one - which by the way in the desperation and oxygen debt of the final 80 or so meters of a 1500m race is understandable. She does also then "realign" after that and clearly does look to reestablish the center of the lane which closes down space Hollingsworth believe she finds.
I always try and break this down into "instinctual" vs "deliberate". If it's deliberate then by simple logic Hull has impeded CH and if she trips, it's her fault. If it's instinctual then CH has just misjudged the circumstances and it's her fault.
In this case I don't think anyone can look at the front on footage (out there on social media etc) and say "Hull actively looked to shut down her space". The move across the lane is so imperceptible and completely instinctual, I have no problem with it. It wasn't George Mills basically sidestepping 2 feet across lane lines to get position like that London 1500m last season where he bought guys down. This was like Jakob not allowing Hocker through on the inside of the Paris 1500m final which I personally believe he has every right to do as he'd earned the front of the race - as Hull has done here. I don't even find Hulls shift careless.
What is careless is this increasing trend of looking to find space between runners in lane one and the rail, which is literally an effing rail. That is stupid, careless and dangerous. Hollingsworth could have easily stepped on that little 3 inch wide piece of aluminum and caused even more havoc, including really hurting herself. In the end she takes a slightly "better" option which is to run diagonally across the back of Hull and yeah, no kidding that is going to happen. Bigger picture I just don't understand why these athletes (like Hocker, Hollingsworth) who clearly have the physical ability to win these races, are even putting themselves in this position. If she had positioned herself better with only a slight variation in positioning, she wins by 2-3 meters, Hull gets second and we have the right result.
Now we have Hollingsworth which a highly debatable nation title and Jessica Hull gets nothing, which just can't be right.
Athletes need to take more care, and even though CH of course didn't mean to do this, she did, and this was her fault and there has to be some accountability which will embed in her subconscious to the degree she won't do it again (even though you'd think it might have with Cole Hocker but it seemingly hasn't). Wrong decision here (to reinstate) and with Commonwealth Games selection on the table it's obvious it's a political one/beyond the events on the track - but it's Athletics Australia who always seem to find a way to create team selection drama so no surprises at all on that level.