Fail: SEO is broken on hakanai

I admit, I feel silly. I realized this week that the SEO for hakanai.io was completely broken ^^

SEO is theoretically my sole and unique acquisition channel for the SAAS. But:

• 10 months after purchasing the domain name, I still have a mediocre domain rating: 14, compared to 36 for Bloggrify and 29 for my own blog.
• if I search for the name hakanai, I don't even find hakanai.io in the search results.
• I get 400 unique visitors per month while I was getting double that at the beginning of the year. The decline started in June.

Not great...

I just discovered that a large part of my pages have been deindexed.

I don't know why. I wonder if Google didn't at some point consider the site fraudulent, perhaps because of the pSEO (programmatic SEO) that I had implemented with the Blog starter Kit. It also seems to correspond to the moment I moved the documentation, the blog, and the blog starter kit to subdomains.

I made this choice because it was technically simpler and many sources online seemed to say that subdomains and subdirectories were equivalent for SEO. There are quite a few conflicting opinions on this. What is certain is that the current result leans more in favor of subdirectories...

Anyway, I'm trying to fix it urgently. I've moved the blog and documentation back to subdirectories. And I set the entire blog starter kit to noindex to see if that changes anything. That was a week ago. For now, no result. It's a bit worrying. Let's see...