I created a new site - maybe in vain, it was necessary to push the pages onto the old one?

Question

Search Engine Optimization

I made a site for a separate topic with a "human-understandable name" type - financial-model.rf
Type of landing for individual services, etc. But a vague doubt gnaws - maybe it was necessary not to play the fool, but to place all these pages on an old site that is already 15 years old, and which is in the top of all major commercial low-frequency speakers?
Even if these pages do not rise in the search results, at least I will drive them with links from longreads that people actually read?
Or still try to promote - like two sites - not one site :)

Answer 1

You have not chosen the main goal, decide and ok