That is insane how off they can be. I would sure as hell never trust one after results like that. I would maybe consider having it (if you found a more accurate one) as a over time thing to track all day but I would know that its not very close. Its more like "you are low or high" without meaningful numbers.
I see people use them to test foods and how the affect their blood sugar in YouTube and they look reasonable. But they always show the graph and don't check with a finger prick now and again. The graphs for us looked okay if you blurred your eyes and didn't look at the numbers but it was still way off from the finger pricking.
I don't prick much anymore because my numbers were so stable. Messed up but stable. I'm trying to fix some other issues so maybe I a couple of weeks I'll pull the glucose meter out again, but even with the ease of the continuous (it was also expensive even with fancy insurance coving a lot of it), I wont bother asking about one again. I can just poke a few times a day. You do get pretty used to it, even if your fingers look weird up close.