I think to some extent, you are confusing demographics. A proper design video might get a very high percentage of your primary audience (i.e., us). That's good, right?
Nope, you'd be wrong.
Because my channel was never intended to be, and was not built on tutorial or design videos, I have a
very diverse audience, and this is evidenced by that stats across practically all of my tutorial videos.
Take for example my Opamp tutorial, by far my most popular tutorial video with an insane 572,000 views, and the tutorial video I get the most thanks for.
Where did all those views come from?
Was it from my core audience of subscribers? Nope, it only got about 50k views or so in the first few months which was pretty average for one of my videos at the time, nothing special at all.
The views came from continued upping in the magic youtube search engine algorithm over time, which ironically is dependent partly upon the number of views I get per day on average, the interaction, the thumbs up etc. And of course, mostly because it's opamps, a very basic and widely searched topic.
i.e. >85% of those views came from search and youtube suggested, not from my subscriber base.
If I went and did a series of videos over the next few months of some niche hard core tutorial topic (possibly PID control as mentioned), and it was the most brilliant content ever, the views and my channel would go down the toilet. Well, it wouldn't be that bad, but I hope you get the drift.
In fact if I did
nothing but tutorial videos for the next 6 months it would be the same fate.