No , there is no penalty for this.
focusing on one topic is a good strategy as long as you make every video new, like you said a different angle, this is one of the many strategies that even big content creators do, focusing on the one topic that got them very high views in the first place, the only problem of the videos not getting views would be if the viewers some how feel that all your videos have the same points and this can bore them, so yeah as long as you bring it out in new and different ways, you can keep talking about the same topic, youtube isn't going to limit your views for that.
Do not make multiple videos on same topic. Related topics you can cover in different videos. Try to educate the audience about something new, they will also remain attached to the channel because of this.
For example, if your channel is about making money on YouTube, you can break that into many subtopics. But if you keep posting videos on one fixed topic (like creating Gmail accounts), it might hurt your channel since the content becomes repetitive.
Staying in one niche is actually smart YouTube prefers clear signals. If views dip, it’s likely the angle or execution, not the topic. Keep the theme, just refresh how you present it.
