I think this file might have been improperly converted. If I run from your branch/fork:

git log --follow --oneline -- docs/source/mobile_optimizer.md

I only get one item in the git log:

71c7477c84f convert mobile_optimizer.rst to mobile_optimizer.md

But if I run from main for the .rst file I get:

0d193a0adf0 Add ExecuTorch warning to mobile_optimizer (#134697)
da43584bef3 [Reland] Clean Up MobileOptimizerType Rewrite Flags Public API and Documentation (#92081)
4f91b8e0ee8 Fix typo under docs directory  (#91871)
3aeb7127b44 Revert "Clean Up MobileOptimizerType Rewrite Flags Public API and Documentation (#91600)"
370df963e06 Clean Up MobileOptimizerType Rewrite Flags Public API and Documentation (#91600)
df1cc0ef473 [Vulkan] Add Vulkan Rewrite to Transfer Inputs and Outputs to Vulkan and CPU Backends Respectively (#87432)
b3387139b42 Mod lists to neutral+descriptive terms in caffe2/docs (#49803)
79b8328aaf5 optimize_for_mobile: bring packed params to root module (#42740)
04320a47d76 Add optimizer_for_mobile doc into python api root doc (#41211)

We want to preserve history for this file which I think we achieve (more or less) with git mv or any other way you want to propose. All other files I checked in this PR seem to have preserved their git log.

That's weird, I used the same method for all files, ie, git mv
On my local repo too, running the command you mentioned doesn't work for the .md files but they do for the .rst files. Not sure why this is so, and looks like the same issue is happening with others as well

Kindly forgive if its trivial, I'm new to open source

Its due to how Git works. If too many lines in a file is changed Git won't find similarity between 2 files so doesn't show that they were renamed. Git doesn't actually store the history of changes in its database but rather the state of the entire workspace. I tried to explain it here hopefully it helps explain but this is expected.

#155120 (comment)