Once we can put behind the shame of feeling like self-promoting is a bad thing, I think the world would be a much better place (for artists, that is). It's not "lame" to contact a streamer, it's just marketing. What do you think all those mobile games do? They reach out to the streamers.
However, I wouldn't expect a high turn around on that either. In general, giving feedback is difficult for a lot of different reasons:
They might not know what to say. Perhaps they like it, but they don't know why. Perhaps they hate it, but they don't know why. Either way, if they don't know what to say they aren't going to say anything.
They might not have the time. Even if it takes 1 minute to write something, that's 1 minute where they are not doing something else.
They might not know you want feedback. It's not the first thing people think about when they download a game. Usually when they download a game they are more interested in just playing it without considering ways to improve the game. Generally speaking, it's a good idea to encourage users to do something (in this case, give feedback), which we call a "call to action". This is a common practice you'll see influences use often where they ask users to subscribe, like, and comment. Does it get repetitive hearing it often? Of course, but they reason they do it is because it works. If your game is a demo, consider adding something at the start and end of the demo politely requesting users to leave feedback.
Similar to the first point, and something I briefly mentioned in the previous point: users may not want to take notes or think about what could be improved when playing. Playing a game to look for improvement is a lot different than just sitting back and enjoying the experience, and maybe some people are not interested in doing that.
The main thing I would say is: don't be afraid to put yourself out there. There does seem to be a strange internet rule about not self-promoting, but the reality is: if you can't promote yourself, how will people know about you? But at the same time, don't expect a high turn around on feedback.
For some perspective:
My last album I released, I spent 2 months using multiple sock-puppet accounts on reddit, personally emailing musicians, music reviewers, and any influencer with even a passing relationship with music in their content, plus forums, music blogs, and countless other outlets. It was probably the hardest part of the release. At the end of the day, I still only made about 30% more sales over my previous album's release, and to be clear: I'm not a big name, so 30% for me is....not a lot.
My own business I run I often hand mail flyers to people's mailboxes (yep, snail mail spam). The percentages vary depending on the time of year, but I'd say out of 1000 flyers, I get 2 - 3 responses. That's a 0.2% response rate.
Don't expect high turn around from people, but keep trying your best
