Why was Matrix discontinued?

There isn’t a single “Matrix” that was universally discontinued; several different products, services, and media have used the name and were retired at different times. To give you an accurate, up-to-date article in the HTML style you requested, please tell me which Matrix you mean. Here are a few common possibilities:
- The Matrix Online (2005–2009): a mass‑multiplayer online game set in The Matrix universe, shut down by its publisher after years of declining subscriptions and rising maintenance costs.
- The Matrix film franchise or related media: not discontinued as a franchise, but projects and extensions have varied in development and release over the years.
- Matrix-branded products or platforms from tech or telecom companies (for example, Matrix Comsec or similar), which may have discontinued specific models or services.
- Other media or software simply named “Matrix” (educational tools, software libraries, hardware lines, etc.) that were retired for business or technical reasons.
If you can specify which Matrix you’re asking about (for example, “The Matrix Online,” or a particular product line from a company called Matrix, etc.), I’ll draft a full HTML-formatted article in the journalistic style with an introductory paragraph after the headline, properly structured sections, pre-list and post-list paragraphs as you requested, and a concluding summary.