It's the latter. Some people abuse the system by highlighting the full length of every broadcast, turning their highlights section into a complete archive of their streams, which is not something Twitch ever wanted to offer.
I don't think it's fair to say twitch "never wanted to offer" when not long ago, that behavior was the base functionality. You could rewatch everyone's entire streams forever. There was a DMCA scare at some point when streamers were getting in trouble for their old streams having music and many took down all of their history, but before then you'd see years worth of streams for people
I did that, but not as a way to abuse the system. I used to export all my streams to YouTube directly from Twitch without downloading it first. I would just trim the beginning of the stream and sometimes split in more than one video if I had multiple content in one stream. I have hundreds of videos starting from 2018. I just thought this was ok and now I'm going through the effort of exporting them individually to a youtube account. I wish they had offered at least a way to export or download them in batch.
>Asking ChatGPT
That alone makes me want to discard your entire argument, but the answer is pretty simple: cost
Hosting huge amounts of video data throughout multiple data centers is just plain expensive.
Some ads isn't gonna fix that, especially since twitch already has a frustrating amount of ads everywhere.
Every time anyone posts anything from ChatGPT, it gets immediately and massively downvoted. It’s clear the community doesn’t want this; please don’t post it!