A Critical Appraisal of cognitive hierarchy of Bloom's taxonomy is

Bloom's Taxonomy is a recognized and influential framework in educational fields that establishes a hierarchy for cognitive learning objectives. The levels in this taxonomy, in ascending order, are knowledge, comprehension, application, analysis, synthesis, and evaluation. 

Key PointsThe critique "Minimum level unnecessary" refers to the notion that the lowest level of Bloom's Taxonomy - 'knowledge' is not needed.

• According to this viewpoint, merely identifying and recalling information (knowledge level) is viewed as rote learning and not meaningful learning that engages learners cognitively and helps them understand, apply, or create knowledge.
• This critique assumes greater weight in the context of 21st-century learning environments where information is readily available, and the ability to recall facts or data (knowledge) is deemed less critical than being able to evaluate, analyse, or create new information.

In conclusion, the critique highlighted by "Minimum level unnecessary," challenges the emphasis on knowledge acquisition, the lowest level in Bloom's Taxonomy, suggesting its diminished relevance in the modern learning context.