[Arnavion]

Consider replacing your Youtube subscriptions + watching in the browser with RSS feeds of the channels + youtube-dl. [1]

My setup for a few years has been to have a "virtual desktop" for "media" that has the video downloads directory, RSS reader, and a terminal running a script. The script is essentially:

    while read -r url; do
        youtube-dl --... "$url"
    done

The RSS reader is configured with feeds of the channels I "subscribe" to, and configured to only show the titles of the articles, not the content. (I use newsboat with a custom article list to aggregate all articles from all feeds.)

Every so often during the day, I switch to that virtual desktop, check if the RSS reader has new unread articles, copy-paste each URL from the reader to the terminal, delete the articles from the reader list, and then leave the terminal downloading the videos in sequence.

I have DSL but even then videos download faster than I can watch them (which is something youtube.com in the browser is unable to do, even though I configured youtube-dl to download the highest quality <= my monitor size). So I just make sure to queue the videos from the channels that make smaller videos first (ie live action stuff rather than video games), so I can start watching while the rest are downloading in the background.

[1]: Of course you can remain subscribed to the channels on youtube.com if you wish to contribute to their subscriptions count. I assume youtube-dl'ing a video counts towards its views count too.