I would say that there is also some truth to this charge from Dietitians (Dietitians Weigh in on the Low Carb/Ketogenic Diet) . There are prominent proponents of the keto diet who do recommend what I consider to be very low levels of protein (Jason Fung, etc).
Remember that Jason Fung is a kidney doctor and his kidney dialysis patients need to be on limited protein to spare their kidney function. This is not a normal issue for most diabetics.
Studies show that the US RDA for protein are too low (Are the Protein RDA Values Enough?). I’ve written at length on the value of protein for diabetics (High Protein Diets are Good for Type 2 Diabetics).
Keto is not inherently low protein. And a Dietitian could and should recommend higher levels of protein.
The keto community should have a protein summit and let all of the proponents debate this subject. I am convinced that if the facts get out that protein will remain king.
In the meanwhile, Dietitians can recommend ketogenic diets with the caveat that higher levels of protein are generally beneficial for diabetics. It’s probably even more important that dietitians teach people how to know how many grams of protein that they are getting.