This rule, to be carried out this month, applies to all the YouTubers, regardless of their location or their content (even if it is directed towards a mature audience). This sudden declaration has caused quite a big conundrum in the virtual world. According to the rule, YouTube can demonetise the content of YouTubers who fail to follow it and might even get fined.
Carbonite is online backup only, so it doesn't really work well for local backups or backups to external drives. You'll still have to handle that yourself. You can try Carbonite for free for 15 days, but after that you'll need to pay up $60/yr to back up one computer with their Home plan, $100/yr to back up one computer with their Home Plus plan, and $150/ur to back up one computer with their Home Premium plan. You can read more about Carbonite's plans and pricing here.
To protect your channel from COPPA, you can download all videos in the channel to your computer for backup or re-upload them to other platforms. Since online websites do not support batch downloading of videos, and most of them have suspicious and unsafe ads embedded, thus, it is better to use a safe and reliable tool like Jihosoft 4K Video Downloader.
The next page will show a list of all Google products associated with your account whose data can be backed up. All of them will be selected by default, so make sure to unselect all and select only youtube. An easy way would be to untick the "Select All" button at the top which will unselect all items. Then scroll down and check the "YouTube" option.