Kata is preplanned activity concerned with idealised methods and ideas. In judo uchi komi are extremely formalised. Beginners learn specific basic stepping patterns and only later have enough idea of the concepts behind the basics and enough technique to be able to apply them freeform to a decent degree. Improvisation is based on the ingraining of basic formalised technique- kata. Uchi komi are used even by good judoka to re familiarise with proper form.
In bjj guard passing is extremely formalised. Jiu-jitsu even names and formalises the specific passes. A beginner learns the basic idealised methods before being shown variants or being able to come up with their own answers based on internalised concepts. Form training (or drilling of the basics) is completely necessary in order to develop technique. However it doesn't work without increasing resistance drills and finally application is a fairly free environment.
In some "trad" MA (some karate for example) the kata have somehow become the whole activity. There is no learning progression from form to free movement and there is no drilling with resistance. This is the only real problem, not the kata themselves. I think most of you on this thread just don't like the word kata because it has become associated with bad practice and misunderstanding.