Rewards a few hours ago were around 1.7 Mrai per recaptcha.
It costs about $1.2 for services to solve 1000 recaptchas for you.
So for 0.0028 BTC ($1.2) you get 1700 Mrai which means you're breaking even at 165 sats per Mrai.
And it's safe to say that at such low rewards as 1.7 (which translate into over 200 recaptchas being solved every minute) only captcha solving services and maybe some super enthusiasts are solving recaptchas.
With all that said I think the price will decrease probably below 200 in a few weeks.
I really love your analysis. However, I would like to present a different point of view.
This is a question of demand and supply. You are saying that the price should drop, but I would argue that it would only do so if there was no demand. If there is demand then instead of price falling down, the rewards will fall down until they find an equilibrium.
If you are saying people will gladly get paid $1.2 for solving 1000 recaptchas, then they'll provide more and more supply, until it reaches that price. The comparison to Bitcoin mining is fascinating. The difficulty of the network self-adjusts.