Unlike Reddit, Apollo was stopping users from seeing ads and Reddit gaining ad revenue from them, so they went to charge the Reddit app devs for this loss in revenue.
The YouTube embed API supports ads, and works perfectly with Premium so Google are not losing any potential revenue with this app existing.
Sounds like Christian learned his lesson with his experience with Reddit: "don't get in the way of the company's ad revenue".
Your statement still stands though, you are ultimately correct.