They can only do so acutely until the blood sugar drops. It will not matter in the long run if there is a calorie deficit. I like to summarize it like 24 hour calorie balance is far more important than short term acute effects.
I think that's right, but it's worth noting that "until the blood sugar drops" is doing a lot of heavy lifting there. That varies a lot by person. E.g. I wear a CGM, as does a friend. We can eat the same thing, and my friend's CGM reading drops back to his baseline in less than an hour while mine stays elevated for several hours.
I eat low-carb foods and intermittently fast to compensate, but if I ate a "mainstream heatlhy" diet (3 meals a day, grain bowls, etc), my blood sugar would be moderately elevated for most of the time.
They can only do so acutely until the blood sugar drops. It will not matter in the long run if there is a calorie deficit. I like to summarize it like 24 hour calorie balance is far more important than short term acute effects.