Just an update: Logging out in the non-functional YouTube app in Gingerbread made it impossible to log in again. The error message (roughly translated) reads:
A problem occurred during launch. Check the network connection and system time.It seems to me, that Error 410 probably appeared when an account is set as logged-in in the YouTube app, though I cannot claim this for certain. The error cited above now appears when attempting to log in, or when trying to play videos.
On the other hand, I got yet another opportunity to check out a device with Android 4.0 Ice Cream Sandwich (ICS), and the YouTube app does work there, provided, that some of the software components are kept up-to-date.
The example ICS setup with a working YouTube app has the following component versions:
* Android 4.0.3
* Google Play Store 8.0.76.R-all [0] [PR] 163912422
* Google Play Services 14.5.74 (000302-219897028)
* YouTube app version 11.01.70
People with Android 2.3 Gingerbread and a non-functioning YouTube app can do the following:
• Continue using the mobile YouTube site in the default browser that would launch videos in an external player.
The reason I suggest using the default browser ("Internet"), is, that while older versions of Mozilla Firefox and derivatives can run on Android 2.3, and while they do also support HTML5 video, then Firefox is resource-intensive on low-end devices. Such devices do not have enough RAM memory, and/or cannot run anything greater than Gingerbread. With these, video playback might work in Firefox, but not satisfactorily, or might not work at all.
• Or they can upgrade to at least Android 4.0 — either by updating the software, if a device manufacturer and/or mobile operator has an update on offer; or by obtaining a device installed with at least ICS.
This I left out of the reply:
It appears, that this time, the YouTube app not working on Android Gingerbread is final, hence 'no longer' in the title of this post. I don't think it will be fixed, and it would be a miracle, if it were. If someone has Android 2.3 with a working YouTube app, while most others don't have that, then the most likely explanation could be expired certificates in the app and Gingerbread itself, and updated certificates on the YouTube end. Such is life.
In this case, I follow a personal policy of not suggesting alternative apps. Therefore, if the official app doesn't work, use the browser.