Yes. Moderating a large sub is a ton of work with no compensation whatsoever.
The biggest sub I mod recently grew to ~10k users, it's German speaking, and covers a pretty niche topic.
That sub alone is already a surprising amount of work, and 10k is absolutely tiny.
Automod alone removes 4-5 posts a day, and there's still quite a lot of bot generated, irrelevant, or spammy posts and comments that manage to bypass the filters. I can't imagine the amount of spam that would flow in at a subreddit hundreds of times larger than that.
The biggest sub I mod recently grew to ~10k users, it's German speaking, and covers a pretty niche topic. That sub alone is already a surprising amount of work, and 10k is absolutely tiny.
Automod alone removes 4-5 posts a day, and there's still quite a lot of bot generated, irrelevant, or spammy posts and comments that manage to bypass the filters. I can't imagine the amount of spam that would flow in at a subreddit hundreds of times larger than that.