Reddit or X - where would you market a product like this first with zero audience?

I’ve built a product called VIViD. (www.askviv.id)

It is a unique work and career assessment for people who feel something is wrong in their work, but are not sure whether the problem is the role, the company, the manager, the environment or a pattern they keep repeating.

It is not a quick personality quiz.

The user answers over 100 written questions, then VIViD asks adaptive follow-up questions based on their actual answers. The final report gives them a clearer view of their identity at work, the environments they are likely to thrive in, the friction patterns holding them back and a practical 90-day roadmap.

The product is live, but I am starting from zero audience.

No following on X. No Reddit presence. No email list. No existing community.

So my question is:

For a product like this, would you start with Reddit or X?

Reddit feels better for finding people already searching around burnout, career change, toxic workplaces, job dissatisfaction and identity after work.

X feels better for building in public, founder storytelling and longer-term audience building, but maybe less direct for finding buyers now.

I am especially interested in hearing from people who have marketed something thoughtful, personal or assessment-based without already having an audience.

Where would you start, and why? and HOW?

thanks