"Internet" keto can be whatever you want it to be. 20g total carbs (3 cups veggie), 20g net carbs (which gives you more veggies), carnivore, whatever. Why it’s popularity is waning, people try it and think they need to add buttered coffee, or purchased fatty shakes.

Therapeutic keto used originally for epilepsy and now some other disorders has an exact formula, the strictest of the five ketogenic definitions here: https://charliefoundation.org/