I’ve streamed a little bit on Twitch but got too busy to do it regularly so I never accrued a huge following or anything so take anything I say with a grain of salt.
Starting out and getting traction is always the hardest part. If you don’t have people coming in through other social media, people only find you by specifically looking through the creative category and then choosing gamedev. And then they have to find you inside among the other dev streams. Compared to gaming streams, dev streams get waaay fewer viewers. Also, I’ve noticed that most of the people who will watch those streams aren’t gamers, but other developers. Which makes sense considering those kinds of streams are usually not very entertaining and only really insightful for other devs. Moreso than videos on youtube, twitch streams create lots of “dead air” while the dev is quiet and thinking.
I’ve watched a few dev streams, but by far the most watched and popular had been by Vlambeer when they regularly streamed while working on their game Nuclear Throne, which had been in Early Access at that time. This stream also attracted gamers because the game was already out and popular so people were invested, and they felt like they could weigh in on the development process during those streams.
There are also devs who will document their progress on youtube, but I’ve yet to see one who gained a lot of followers. Again, devs seem to watch these videos rather than gamers.
Also, it’s a lot harder to make money on Twitch than it would seem. There are conditions for getting partnered with Twitch (iirc you have to stream at least 3 times a week and you have to consistently get more than 500 viewers, though they might have changed those conditions so don’t take my word on that) and outside of that, you could open up a donation box, but without a following in the first place, that might not yield great results.
In the end, it really comes down to the fact of whether you like to stream while working on your game. If the thought sounds stressful or uncomfortable, you probably won’t lose out on much. But if you want to stream, do it for the joy of it but don’t expect anything.
Software-wise I’d recommend OBS. It’s free, it does what it’s supposed to, and most people on twitch use it. The initial setup takes a while, but after that, it should be smooth sailing.