According to internal documents, the new Twitter Blue now has fewer than 300,000 subscribers.

When Elon joined the firm, it was losing $4 million per day, resulting in major layoffs and a search for income-generation solutions. Paid verification makes reasonable, but Elon has also expanded the need for instant payment into a road to combat bots, by employing verification to verify all the genuine humans’ – i.e. bots won’t pay, and bot peddlers won’t be able to afford such at scale.
Most individuals will refuse to pay, especially when you’re offering nothing more than an image of a tick next to their username, and the act of selling verification ticks removes its only perceptual value.

Now that everyone can buy one, the tick is meaningless, at least as a type of status signal.
A recent story from The Information has vindicated my position on this, at least at this early stage, stating that according to internal documents:
Travis Brown, a researcher, has been releasing regular updates on Twitter Blue subscriber counts, which are based on searches of individuals who appear as ‘blue verified’ in the back end.
Based on Brown’s estimates, the new Twitter Blue program appears to have roughly 300,000 subscribers, which is quite close to the data obtained by The Information.

Elon stated in the initial outline of his Twitter 2.0 reformation plans that he wants subscription money to be roughly 50% of Twitter’s entire intake. That would be in line with the aforementioned income and bot-fighting potential, but it would require Twitter to grow Twitter Blue’s take-up by 81x its current level.
300k sign-ups is also barely 0.12% of Twitter’s active user population, so revenue-wise, it’s nowhere close to fulfilling targets, and as a bot disincentive, it’s nowhere near meeting its aims. And, while Twitter Blue was recently expanded to more regions this weekend, there’s no chance it’ll ever reach the levels required to make it a serious consideration in any regard.

The churn rate will be high as well, because a blue tick is no longer valuable if anyone can buy one, and unless Elon and Co. have some magical updates to build into Twitter Blue in the future, beyond Blue-only polls or paying to qualify for monetization, I don’t see how this becomes a significant component of Twitter’s overall intake or process.