What are the odds that they still count those unused accounts towards that crucial user growth metric?

Worked for a CEO that used to require his Customer Service to create new accounts whenever a user would request their account be deleted. You can imagine where the company ended up when the CEO's solution to people wanting to delete their accounts is to replace them with fake ones for the vanity metrics.

Space in databases is essentially free.

... and they can say to investors "we have N million accounts".