My understanding is that the design is fundamentally flawed; the engines are too large to fit under the wings with the existing landing gear, so they were moved forward, thereby upsetting the balance between the center of thrust of the engines and the center of lift of the wings, thereby requiring a brittle MCAS system to attempt to compensate.

The MCAS system itself is flawed in a number of ways, but the core problem (in my opinion) is the attempt to fit large engines under a too-small airplane, in the name of saving regulatory / training costs.