It turns out YouTube has a hidden feature that allows one to subscribe to a channel via RSS. I can understand why it has to be hidden — it's too easy a way for a user to avoid ever seeing YouTube’s algorithmic feed. However, it hasn't completely gone away (as, e.g., a way to export subscriptions has), so let’s make use of it.
Give your RSS reader this link:
where CHANNEL_ID is a part of the URL of the channel right after /channel/. For example, the link to the RSS feed of Tom Scott’s channel — the first one of those I watch — https://www.youtube.com/channel/UCBa659QWEk1AI4Tg--mrJ2A, and the ID is UCBa659QWEk1AI4Tg--mrJ2A.
Sometimes if you come to a channel you will see something completely readable in the address bar instead. Then, to get an ID, you need to click a video and then go back to channel following the link above its description.
Consume content online via RSS — it's far more pleasant than to do so via algorithmic feeds.