Youtube Country Blocking and Complete Take-down Notices
Yes it is worth disputing. Sometimes just filing the initial dispute will resolve it. Here is a great write up of a vidder who went the entire distance. Even if you want to only fill out the initial paperwork, it will help.
https://vidders.github.io/articles/vidding/legal.html
In the meantime, here's what you do
1. Create an AO3 account. You will use this to embed your vids and link to it in your vids posts. This is where people will leave you comments and feedback...that way, if your vid is taken down, you only need to update the new in one location (your AO3 post). And your comments and kudos won't get deleted.
2. Host your vid in two locations - vimeo or vidders.net can be one. The other should be Critical Commons. I'd embed Vimeo/Vidders.net and add Critical Commons as a link to any vids post. If the vid is blocked in only a few countries, add a link to your AO3 placeholder in the notes section (If your vid is blocked in X and Y country, head over here for alternatives). Critical Commons info: http://www.transformativeworks.org/critical-commons/
3. Touch bases with Vidders.net about backing up your entire YouTube channel - including comments.
4. Also more Youtube tips here:
https://bironicwastaken.tumblr.com/post/149269201721/notes-towards-contentids-effects-on-vidding-fx (2016)
http://fan-flashworks.livejournal.com/469321.html (2015)