I suppose if you are regularly consuming sweeteners instead of sugar then drinking straight glucose would cause a dramatic spike in blood glucose levels relativ

I suppose if you are regularly consuming sweeteners instead of sugar then drinking straight glucose would cause a dramatic spike in blood glucose levels relative to sugar consumers. The gut microbiome must include bacteria who also feed on glucose. So diminishing it's population via sweetener consumption and then spiking glucose would be more dramatic than a microbiome that's accustomed to buffering sugar spikes.