API/BUG: infer_dtype_from_scalar with non-nano
- [x] closes #51196 (Replace xxxx with the GitHub issue number)
- [ ] [Tests added and passed](https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#writing-tests) if fixing a bug or adding a new feature
- [ ] All [code checks passed](https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#pre-commit).
- [ ] Added [type annotations](https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#type-hints) to new arguments/methods/functions.
- [ ] Added an entry in the latest `doc/source/whatsnew/vX.X.X.rst` file if fixing a bug or adding a new feature.

Needs whatsnew and targeted tests, opening to see if there are opinions about doing this as a bugfix or waiting to do it as an API change in 3.0
This pull request is stale because it has been open for thirty days with no activity. Please [update](https://pandas.pydata.org/pandas-docs/stable/development/contributing.html#updating-your-pull-request) and respond to this comment if you're still interested in working on this. @MarcoGorelli thoughts on if/how this is worth pursuing? sorry, missed this. I'd have thought this was fine as a bug fix - I'm at jupytercon next week though so may be a bit slow to review, but will take a look when I get a chance 🤔 not sure if this might be related
```
FAILED pandas/tests/frame/methods/test_reindex.py::TestDataFrameSelectReindex::test_reindex_tzaware_fill_value - ValueError: Unexpected value for 'dtype': 'int32'. Must be 'datetime64[s]', 'datetime64[ms]', 'datetime64[us]', 'datetime64[ns]' or DatetimeTZDtype'.
``` Thanks @jbrockmendel 