you should read up on slipper slope fallacy
"Logic and critical thinking textbooks typically discuss slippery slope arguments as a form of fallacy but usually acknowledge that "slippery slope arguments can be good ones if the slope is real—that is, if there is good evidence that the consequences of the initial action are highly likely to occur. The strength of the argument depends on two factors. The first is the strength of each link in the causal chain; the argument cannot be stronger than its weakest link. The second is the number of links; the more links there are, the more likely it is that other factors could alter the consequences.""
https://en.wikipedia.org/wiki/Slippery_slope#Non-fallacious_...
I can also see them collecting code searches done within the app as a way to check if their search system is working well for real use-cases.
Neither is outside the realm of possibility - you just have to put yourself in the mindset of a dev who is assigned to track down a rare crash or to “improve the search experience” who might want a little more data to work with.
Not saying I agree with any of this collection - it’s terrible and definitely falls under “the road to hell is paved with good intentions”. Companies should be extremely clear about what they will and won’t collect - and never cross the line even if it would be useful.