I depend on a pump and CGM (currently that's a Dexcom G7 and Omnipod, but I've used other brands as well).
I like the technology, but you have to 1) know your own body and 2) verify if you are uncertain about the readings. Every time I've switched devices I've interacted with diabetes educators, and they pretty much always tell me to always be prepared to verify manually (with an old-school finger stick and test strips).
Additionally, it's not always the fault of the technology, but often where meatspace and technology interface. When you insert a CGM, there's always a risk of the canula not going into the skin correctly. (usually it's a spring-loaded insertion tool and shoot a needle into your skin quickly, but it can mess up if the amount of pressure applied is wrong etc)
In such a case, the sensor that measures your blood will often, where you can't see, sit on top of the skin. This results in insanely low readings. That happens to me a few times a year (I swap out the sensor every 10 days), and you have to listen to how your body feels relative to the readings, and replace the sensor if necessary.
I wear a Freestyle Libre. Even during their mandatory onboarding, they warn about incorrect readings for the reasons you described and urge you to verify the glucose level with manual measurements when in doubt. Also, it's better to just eat glucose when the CGM shows a rapid decline or low level, even if it's due to an inaccurate measurement. This is in contrast to accidentally applying too much insulin and forcing a low glucose level. Of course, low levels often present with very obvious symptoms.
However, the FDA announcement warns about constantly low measurements. Unfortunately, the announcement does not explain what 'low' means in this context and what the actual issue was (it might be technical with the sensor or with the applicator). If it means that glucose levels are too low in terms of 'alarming low', this should prompt manual measurements. However, if the measurements show incorrect levels within the 'normal' range, this is a much bigger issue with these devices. This could explain why affected people have changed their diets or medication plans. These changes should always be discussed with a physician, though. Disease management programs can catch this (e.g. quarterly measurements of HbA1c).
CGMs are helpful. But they require knowledge about their limitations, especially for people who need insulin. They helped me to bring my glucose levels back into normal range without the need for any medication. I hope, I can keep my insulin intolerance at bay for a long time this way.
I like the technology, but you have to 1) know your own body and 2) verify if you are uncertain about the readings. Every time I've switched devices I've interacted with diabetes educators, and they pretty much always tell me to always be prepared to verify manually (with an old-school finger stick and test strips).
Additionally, it's not always the fault of the technology, but often where meatspace and technology interface. When you insert a CGM, there's always a risk of the canula not going into the skin correctly. (usually it's a spring-loaded insertion tool and shoot a needle into your skin quickly, but it can mess up if the amount of pressure applied is wrong etc) In such a case, the sensor that measures your blood will often, where you can't see, sit on top of the skin. This results in insanely low readings. That happens to me a few times a year (I swap out the sensor every 10 days), and you have to listen to how your body feels relative to the readings, and replace the sensor if necessary.