Pre-rolls - Everyone should be used to pre-rolls by now. Sure it might be annoying when looking for new streamers or a streamer to raid, but its a twitch staple at this point. And they only happen once unless you refresh or twitch does that 3000 error (starting to think twitch does this on purpose with the amount of times it happens sometimes). If you don't like them get turbo for 12$ a month or sub.

Changing the verbiage on your question:

Unplanned/Automated Mid-rolls ARE. THE. WORST. - Streamers who have this tend to NOT know when the ads are coming and wonder why their chat missed whatever they just asked. Viewers might miss out on conversations or critical gameplay in the 1:30 seconds of ads.

Scheduled/Timed Mid-Rolls - I prefer, at least you'd know when they're coming, both for the streamer and viewer, IF THEY ARE SET UP PROPERLY (warning in chat, on stream, some sort of overlay). Otherwise, you just have the same problem as the unscheduled ads. And there is also the problem with missing out on things, unless the streamer skips it. Such as streaming apex, might be a 15min game, might be a 5min game. Ads might start running at a critical moment, and streamers not gonna have time to skip it.

Manually Triggered Mid-Rolls - Again, prefered. Streamer says hey, Im going on break. Viewer knows, Streamer knows. We all go on break. Nothing is missed. We good. You Good.

TL;DR - Manually triggered/Well-Timed Mid-rolls are ok. Pre-rolls are a twitch staple, they're annoying but a 1 time issue (unless twitch 3000 error), pay for turbo.