While the patents may not be enforceable, this can only be determined through a legal process, which is expensive and time-consuming. It may also be possible to achieve the intended results without infringing Microsoft's patents.
The lack of enforceability of patents doesn't mean they are invalid; it requires a legal process to confirm this, which can be costly and time-consuming.  Alternatively, achieving the desired outcomes might not require infringing on Microsoft's patents.