Repository: yt-dlp
Issue: [core] Default --trim-filenames values
Labels: enhancement,core-triage

### DO NOT REMOVE OR SKIP THE ISSUE TEMPLATE

- [X] I understand that I will be **blocked** if I *intentionally* remove or skip any mandatory\* field

### Checklist

- [X] I'm reporting a bug unrelated to a specific site
- [X] I've verified that I have **updated yt-dlp to nightly or master** ([update instructions](https://github.com/yt-dlp/yt-dlp#update-channels))
- [X] I've checked that all provided URLs are playable in a browser with the same IP and same login details
- [X] I've checked that all URLs and arguments with special characters are [properly quoted or escaped](https://github.com/yt-dlp/yt-dlp/wiki/FAQ#video-url-contains-an-ampersand--and-im-getting-some-strange-output-1-2839-or-v-is-not-recognized-as-an-internal-or-external-command)
- [X] I've searched [known issues](https://github.com/yt-dlp/yt-dlp/issues/3766) and the [bugtracker](https://github.com/yt-dlp/yt-dlp/issues?q=) for similar issues **including closed ones**. DO NOT post duplicates
- [X] I've read the [guidelines for opening an issue](https://github.com/yt-dlp/yt-dlp/blob/master/CONTRIBUTING.md#opening-an-issue)

### Provide a description that is worded well enough to be understood

Currently --trim-filenames is disabled by default, which can lead to "file name too long" errors with the default output template, as shown below. I believe the option should be enabled by default (once the linked PR is merged, as the current --trim-filenames is pretty broken) to prevent errors such as this. As for what the default should be, I will copy what I wrote in my initial [PR](https://github.com/yt-dlp/yt-dlp/pull/12023) for this issue:

> Furthermore, I have added (what I believe to be) reasonable default values for `--trim-filenames` based on the platform of the user. Based on this [table](https://en.m.wikipedia.org/wiki/Comparison_of_file_systems#Limits), it seems that for Windows and Mac filesystems (NTFS, FAT32, exFAT, HFS+, APFS) the maximum filename length is 255 characters, while the majority of other filesystems have a maximum filename length of 255 bytes. I also subtracted the length of what I think is the longest possible extension (`.annotations.xml`). I think these defaults will be fine for the majority of users and will prevent filename too long errors.

See also the brief discussion here: https://github.com/yt-dlp/yt-dlp/pull/12023#discussion_r1906957589

> @pukkandan: Changing default needs some further discussion (such as not truncating `id`, adding `compat-option` etc). It'd be best to split it off into a separate issue.

> @7x11x13: IMO failing to download is a lot worse than truncating the videoId in the filename. Perhaps the default output template should have the videoId at the beginning of the name, rather than the end? Anyways, I will split this into another PR.

Related:
- https://github.com/yt-dlp/yt-dlp/issues/1136

### Provide verbose output that clearly demonstrates the problem

- [X] Run **your** yt-dlp command with **-vU** flag added (`yt-dlp -vU <your command line>`)
- [X] If using API, add `'verbose': True` to `YoutubeDL` params instead
- [X] Copy the WHOLE output (starting with `[debug] Command-line config`) and insert it below

### Complete Verbose Output

```shell
yt-dlp "https://7x11x13-testing.bandcamp.com/track/-"                                                          
[Bandcamp] Extracting URL: https://7x11x13-testing.bandcamp.com/track/-
[Bandcamp] -: Downloading webpage
[Bandcamp] 953563459: Downloading free downloads page
[Bandcamp] 953563459: Downloading mp3-v0 JSON
[Bandcamp] 953563459: Downloading mp3-320 JSON
[Bandcamp] 953563459: Downloading flac JSON
[Bandcamp] 953563459: Downloading aac-hi JSON
[Bandcamp] 953563459: Downloading vorbis JSON
[Bandcamp] 953563459: Downloading alac JSON
[Bandcamp] 953563459: Downloading wav JSON
[Bandcamp] 953563459: Downloading aiff-lossless JSON
[info] 953563459: Downloading 1 format(s): falac
ERROR: unable to open for writing: [Errno 63] File name too long: '7x11x13-testing - ああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああああ [953563459].m4a.part'
```