The math has already done about how boosts make bot accounts far more profitable. I don’t know if I’m allowed to link to it or not, but a simple google search will yield what you’re looking for.
But since you ducked, I’ll ask again: how do you know Blizzard doesn’t want to fix the problem? Because I tried to do a little research to see if Blizzard ever did or said anything that suggested they didn’t want to fix the problem, and all I could find was this blue post:
"I’m sorry, but the suggestion that bots help Blizzard make money or can be viewed by the company as even remotely positive is laughably ridiculous. Such an idea illustrates a fundamental lack of understanding of who these people are.
First and foremost, the majority of botting/farming accounts are exploitative. They are usually compromised accounts (meaning they’ve been stolen from normal players, often who are currently inactive so aren’t aware of the theft), or they are created with stolen credit cards.
In both cases, dealing with fraudulent charges costs the company money. That isn’t counting the negative impact is has on normal players, who may get frustrated and quit playing because they don’t want to deal with bots, gold sale advertisers, etc.
No, we certainly don’t make money from them and the amount of resources dedicated towards efforts to deal with them is substantial."
EDIT: Herbalism bots plaguing BFA - #26 by Rufflebottom-bloodhoof is the thread this post comes from.