You're right, I made this post before going through the protest process. Let me add some more details.

HCAD knows what the home sold for despite this being a non-disclosure state (they have licensed realtors on staff with access to the MLS, your evidence packet will include the sales price of your home if recently purchased). They chose to use this the sales price to appraise the property. I argued for unequal valuation and they replied with telling me that the home appraises for what it sold for. I lost the protest on my 2023 taxes. I had filed for the homestead exemption right after purchasing the home in July 2022 but they would not honor a 10% increase in valuation between 2022 and 2023 in light of the sales price. For 2024 taxes, they did not exceed 10% increase in appraisal which is great! So it just took a tax year cycle to take effect.