I'm glad you've brought this up. There are two aspects I see about these questions:
Are they on-topic?
Yes, I think so. It'd be hard for me to argue that questions about serverless computing, feature flags and black box testing aren't relevant to the topics of a DevOps-related Q&A site. But...
Are they questions we should encourage?
Probably not, especially in the expert-level private beta phase. The idea is that questions should be setting the tone and showing new users what this site is about.
You could almost say, "We gave DevOps experts a few weeks to come up with the best questions they could—questions which can be used to make the case for creating a new site—and they came up with these.".
Questions like "What is X?" or "Why should I use Y?" do not make the case. The blog post Are Some Questions Too Simple? makes this point well in my view, so I'll quote it here:
The key distinction to make here, in my mind, is that all questions are ultimately in service of the people answering them. That is the audience you need to satisfy if you want to have any hope of creating and sustaining a community of peers learning from each other. The minimum bar for a question is not “is this on-topic?”, but rather “is this somewhat interesting and on-topic?”. I’m not saying every question needs to be utterly fascinating, but please endeavor to make your questions more than a constant stream of no-duh underhanded softballs requiring nothing more than a quick cut and paste from Wikipedia, IMDB, or some other standard internet reference site.
There’s nothing useful any expert can learn from ultra-basic questions. Allow your Q&A; community to fill itself with enough “General Reference” type questions and you’ll soon find no experts there at all.
(emphasis mine)
However, the 'General Reference' close reason was abandoned because it ended up being used to get rid of anything that people didn't like. As stated in this Meta answer, it didn't pan out quite like you might hope, and I would imagine being on the receiving end felt a bit harsh—some users thought your question was too simple, so, no answer for you!
If you take nothing else from my post, I strongly encourage everyone to review the page you were shown before asking your first question:
You get the site you build
The first questions set the tone and topic of a site for a long time. Those early questions say a lot about what your community could become. And questions asked during the private beta will be on the front page when potential experts see your site for the first time. So please make those first questions exemplary ones that are interesting, challenging, and worthy of imitation.
Make this site worth opening up, and it'll do well. Allow this site to fill up with questions that are better answered by Googling, and people will just turn to Google instead.