Okay you are right TD defense is a weak spot, but I was thinking more generally like trying to learn a ground grappling game. Their plan wasn't bad except they just assumed that Conor would get some strikes in, but he did not and even took some. They have to figure out how to strike a grappler, and it's probably not with Conor standing straight up while sticking his hand at the guy's eyes. That might annoy another striker but not someone who's happy to close the distance.
I get your point, and to an extent, you're correct that spending the camp trying to make Conor a world class grappler on the same level of Khabib would have been foolish. I agree with this completely. That said, (imo), it was NOT a good game plan. It was straight up bad. You know the old saying "playing not to lose"? Well this plan was more like "Playing to lose, but not too badly".
If Kavanaugh truly felt that their best chance was to knock Khabib out in the first round (as he mentioned on JRE), the game plan should have focused on understanding the different angles Conor would need to take in order to counter Khabib's takedown entries. This is something that would have played into Conor's strengths, while also helping him to (somewhat) negate his disadvantages vs Khabib. With a few exceptions, Conor has typically had a lot of stylistically favorable match-ups in his UFC career, so he's rarely needed to even worry about adjustments to his style. This was NOT the case VS Khabib, and while Kavanaugh seemed to recognize that, he over-corrected in the wrong direction in my opinion. Instead of a coherent, potentially win-able game plan, he came up with "When you get taken down, just quit". Even in his own estimation, he seems to feel he made a mistake.