While I think the capcha thing is an extremely bad idea, your numbers should probably rather be based on active player counts and not all time copies sold so you're way, way off here. Also consider that the community based stuff is a big part of what actually keeps players around long-term in MMOs and the effects go beyond the individuals here.
Ah perfect! I've been looking for someone to give me the active player count. FDev will only give how many copies have been "sold?". So, how many active players are there? All we have to go off of is the information given to us, otherwise, we're just making stuff up.
But seriously, the group of people who will actually be driven away from the game by BGS botting problems or the actual botting problem itself must be so insignificant to FDev that in the multiple years that people have been complaining about it, FDev has done... what? Well, I guess not much or we wouldn't still be talking about it. And who has been driven away? Was there some mass exodus no one seemed to notice? Seems there are many of the same people complaining about it now as were years ago. Sure, someone might point out 10, 20, or even 100 people by name who quit the game over botting (although I doubt it), but it's not a thorn in FDev's side to lose them, at least not enough to invest money in finding ways to annoy their players with ani-botting hoops. So regardless of the numbers, FDev has shown through their action, or inaction, over the years, that either botting is not a significant problem or the number of people quitting the game must be insignificantly small compared to whatever the "active player" base is and so a solution is not worth the investment. The community is greater than people RP'ing playing the BGS.
...either that, or they have a solution, it took a really long time to implement, and they just aren't talking about it yet but it will be here with Odyssey. However, if I were a betting man, and I am, I wouldn't bet on this being the case.
¯\
(ツ)/¯