Physicians have an ethical obligation not to order unnecessary treatments, especially those that could cause iatrogenic harm. That applies regardless of who is paying. Most tests produce some level of false positives, which can potentially lead to more unnecessary treatments.

From an evidence-based medicine standpoint, how likely are those tests to actually optimize your health?

In this case the doctor explicitly said it was to reduce costs, although the other test is preferable from a diagnosis perspective. Like I mentioned previously, if the reason the doctor gave was that the more expensive test was also less useful or had other negative consequences I didn't think of, then I'd appreciate that. To simply rule out the more expensive test based on cost seemed at ends with what I wanted - again as insurance was paying the tab.

You should ask your doctor! I don't have enough information to give you a confident guess, but my intuition is that theyre trying to save you money when an expensive test is unlikely to be helpful.

Many people struggle to make ends meet, so it makes sense to avoid superfluous medical costs. If you tell your healthcare provider that money is no object I'd imagine that they'd be able to weigh the financial aspect more accurately.