TikTok is like that but it’s loading videos continuously so it makes more sense that it would use a lot. I never noticed significant battery drain with Apollo.
There was a post on the mildlyinfuriating sub where someone had tiktok installed but hadn't loaded it in like a month or something, but it had used a full 2GB of data. Tiktok does more than load videos.
Maybe consider using Firefox for browsing the site instead. The UX can’t get much worse than it already is with the official mobile app. Actually, Firefox won’t be doing sneaky background stuff while you’re not using the site, so the UX should be better in that regard.