After receiving my reply here, I called the provincial tax office as well as the office generating the tax information sheet. Both offices say it was just dropped without warning. No explanation given to either office. Personal opinion based on conversations I've had with those offices, it seems like a happy accident. Expect it to return next year.
For 2022 and beyond, you do not need to enter your Manitoba rent assist payment on your tax return.
You can see the actual 2022 MB479 form here on the CRA's website: https://www.canada.ca/en/revenue-agency/services/forms-publications/tax-packages-years/general-income-tax-benefit-package/manitoba/5007-tc.html
After receiving my reply here, I called the provincial tax office as well as the office generating the tax information sheet. Both offices say it was just dropped without warning. No explanation given to either office. Personal opinion based on conversations I've had with those offices, it seems like a happy accident. Expect it to return next year.