Um, I mean when I had a few hundred subscribers I mostly only got comments on my videos that did well. I'm at 3,000 and I still only get like 10-15 max from other people on a given video within a week. If the video is popular I will rack up more over time, but like in 24 hours after upload I don't really get that many. One thing I've noticed that helps with comments are when I do daily uploads it tends to get a notification squad going who will show up and do the "first", "second", "third" kind of thing. I know that's silly but once you can get some people who come back for every single video and who you interact with a lot you will get more consistent comments.
I play a mobile game on my channel right now and I have a clan in game with people from my channel. I talk with them in there and then they feel more comfortable with leaving comments on the videos I think, or just more invested in the channel. Also when I do a specific video request often the person who requested I'll mention them and they'll comment on the video saying thanks and stuff, maybe starting a conversation. That's one good thing about doing requests is that it builds a bond with subscribers. Once you have some regulars, then leaving a question in the comments will be more effective I think.
Most of my vids under 100 views have a couple of comments at most, and your vid that got 2k views did get some comments so naturally more views will also help you get more comments.