Whoever thinks that trace element dosing and ICP testing do not have significant benefits is either a (over) confident coral whisperer, or is willing to leave a lot of potential progress (and coral health) on the table.
I sometimes feel this is being disregarded/diminished as it does require some work to dial them in at the beginning, so finding arguments to make it less impactful seems easier to do.
I do not believe trace elements dosing and ICP require no or less water change, but opinions vary.
There could be tanks that suffer from this method not because the tank is being dialed properly but due to misuse of the supplementation, potentially overdosing certain elements by not following directions. I do not think there is any tank out there that failed because of properly dialed-in traces, but a lot of them fail or run less well where traces are not dialed in.
Triton, Tropic Marin, and of course Fauna Marin are the only supplementation provider I would use, and for ICP, Triton and Fauna Marin only. Those can be trusted - but they will still make mistake in isolated instances and ICP testing overall is not perfect, but a great tool for those who keep an open mind.