How to reproduce:
1. Open project "render-texture-memory-test.zip"
2. Go to the Build Settings choose iOS, select Development Build and Autoconnect Profiler and build
3. Open build in the Xcode and deploy the app to the device
4. In Unity open Memory Profiler select your device at the top left and press the "Capture New Snapshot" button
5. Select the Snapshot and go to the Objects and Allocations tab and observe the "RenderTexture" size
6. In the Xcode go to Product > Scheme > Edit Scheme and in GPU Frame Capture select "Metal"
7. Deploy the app to the device
8. Press the "Capture GPU workload" button, and press the "Capture" and the "Finish" buttons
9. Go to the Memory tab and observe the "_MyRenderTexture" size

Expected result: "RenderTexture" is the same size in Memory Profiler and in the Xcode's Frame Debugger
Actual result: "RenderTexture" size in the Memory Profiler is 32Mb and in the Xcode's Freme Debugger, it's ~20.3Mb + ~16.1Mb

Reproducible with: 2019.4.37f1, 2020.3.32f1, 2021.2.17f1, 2022.1.0b14, 2022.2.0a9
Could not test with: 2021.3.1f1 (Crash in Xcode after 8th step)

Note: With different Editors, the "RendeTexture" size in the Memory Profiler was different. 2019.4 - 15.7Mb, 2020.3 - 32Mb and in 2021.2, 2022.1, 2022.2 - 48Mb