Can a niche be too nichey?

I agree with 100% of @allison's answer.

Notably, almost every time someone has asked me "is this niche too small" they - just like you! - are talking about an audience that is MASSIVE.

I'd also consider rethinking what you think of when you imagine a "niche" and instead think about the worldview(s) that exist within your topic or category, and focus your energy there: https://stackingthebricks.com/niches-are-for-suckers/

I don't think the size of the niche overall matters. It's the level of value you bring to the people in your niche and your ability to access them. If your product provides so much value that your audience is willing to pay $100/mo for it, then you don't need as many customers.

Looking at Political Startup, I don't think the audience is too small. Politics, lobbying, and activism are huge industries. And with today's political climate, more people are getting interested in these topics. I think the hardest part about running Political Startup would be accessing your audience. If your audience is "marketers who work in politics and government", I'm not sure how you would reach them. Are there keywords you can target for advertising? Are there places online where these people hang out? Perhaps thinking of a niche as an audience, as opposed to a general topic, would help you.

called micro niche, follow revenue / expense rule, if revenue is greater than expense then it is not too-nichey.

Take a look at fellow IHer who started fantasycongress. No niche is too niche. With standardmeta i am targeting people in crypto who are NOT traders. So keep going.

The riches are in the niches.

So, no?