If you stream on twitch, midroll ads make it more difficult to built your stream and hurt your income that would otherwise be from subs, donos, bits, whatever bs twitch is doing. Preroll is better.
You can stream however you want but I've absolutely ducked on some streams I'd otherwise love to watch because of midroll ads. Streaming is about being able to engage, or just otherwise have a conversation with chat and an ad stuffing itself in the middle of a convo just ruins that vibe real bad.
They make twitch money tho, which is why they push for them so hard.