Yeah I'm a bit confused too.
I have 3 different Lemmy apps to test which I like the most and none are as straightforward as Reddit tbh. I'm subscribed to the same things in each one of them, yet they display different feeds. One is even chock full of American politics and nothing I'm subbed to shows up at all.
The only one that feels familiar is the Sync version which somewhat ports across your subs and multireddits (gives you a list of the Lemmy alternatives) and will sprinkle those throughout your front-page feed.
Oh maybe that's it. I've also never seen any kind of popup or ad (same thing for my Samsung TVs) that I've seen people mentioning.
I had no idea why I might be spared.